SAN JOSE, Calif. -- An aftershock was felt in the NBC11 newsroom at 3:54 p.m. Wednesday. The USGS says it was the largest of dozens of aftershocks with a preliminary magnitude of at least 3.7.

The earthquake was located in the same general area of Tuesday night's moderate quake, which is the Alum Rock area of San Jose.

It was by far the strongest of the aftershocks.

There were no reports of damage, but several people called into the station to say it rattled their nerves.

Tens Of Thousands Of Books Fall

Employees at the Dr. Martin Luther King Jr. Library on the San Jose State University campus are cleaning up hundreds of thousands of books that were knocked from shelves during Tuesday night's 5.6-magnitude earthquake.

The library opened today at 9:30 a.m. but with access limited to the first four floors, according to the San Jose Public Library.

SJ Library Books Fall Everywhere | Quake Warning Device | Earthquake Preparedness Pushed | Earthquake Predictors Gather Data | USGS: Quake No Surprise | Clean Up Continues Following 5.6 Quake | Store's Surveillance Video Captures Earthquake (RAW) | Eastridge Mall Damage | Reid Hillview Airport (RAW) | Damage To Safeway, Big Lots (Raw) | SLIDESHOW: Damage Images | Epicenter Map | Calaveras Fault Details

Off-duty employees were called to assist with the reshelving project, which is expected to take several days.

With employees working on the mess, the upper floors will reopen as they are made operational. Most of the fallen books were on the sixth, seventh and eighth floors where the research collections are kept.

After the earthquake, the library was evacuated and the building, which suffered a fallen fixture and a small water leak, was inspected.

Future Earthquake Warning

The California Earthquake Prediction Evaluation Council has a scary warning for people who live on the Calaveras and/or Hayward faults.

They said the, "CEPEC believes that (Tuesday's) earthquake has significantly increased the probability above the normal level for a damaging earthquake along the Calaveras and/or Hayward faults within the next several days."

They went on to say the overall likelihood of such an event is still "low", but did not give a percentage figure.

The U.S. Geological Survey reports 5.6 earthquake based in the Alum Rock area of San Jose hit at approximately 8:04 p.m. Tuesday.

Residents as far away as Sacramento, Sonoma and Los Banos reported feeling the tremor, which is the largest to hit the region since the Loma Prieta quake in 1989.

Worried residents filled the streets in downtown San Jose and found cell phone lines jammed.

"I was scared, I thought I was going to die," Bea Richards said, who lives in downtown San Jose. A water pipe broke in her North Second Street building and things were knocked from walls, including a 2-foot ceramic bust.

Susan Bean with AT&T said that a "traffic jam" is typical after such events and that the system was not damaged during the quake.

Because of the CEPECC's evaluation of the increased risk, the OES recommended that residents of the San Francisco Bay region review their family emergency plans, check their emergency supplies, identify the safe and potential danger spots in each room, remove breakables from locations from which they can fall and cause injury, and stay tuned to the radio or television for further information.

OES also recommended that government agencies and businesses review their plans.

The advisory applied to the following counties: Alameda, Contra Costa, Marin, Monterey, San Benito, San Francisco, San Mateo, Santa Clara, Santa Cruz, Solano and Sonoma, NBC11 reported.

Tuesday night's earthquake shattered glass at the control tower at the Reid Hillview Airport in San Jose.

Chopper11 flew over the tower and showed most of the glass missing. Workers were already hanging plastic sheets over the open tower by 9:30 p.m.

USGS seismologist Steve Walter said the quake hit the Calaveras fault.

Seismologists said it was the largest quake to hit the Calaveras fault since the 1984 Morgan Hill earthquake. That quake was a 6.2.

Send Us Your Damage Photos | Viewer Photos

James Lick High School in San Jose also lost several windows to the earthquake. Workers at the school sent in a series of photos to NBC11.com showing damage there.

There were also reports of items falling off store shelves at several grocery stores in San Jose.

The quake was reported to be 5.5 miles deep, which is shallow in earthquake terms, NBC11 reported.

Many people said the quake lasted around 20 seconds.

Check Out USGS Earthquake Map

The California Highway Patrol has received no reports of damage or injuries, spokesman Tom Marshall said.

The quake was centered in the foothills east of San Jose, not far from the home of the city's mayor, Chuck Reed. He said the city hadn't received any reports of damage.

Pictures fell off the walls of Reed's house, but the mayor said there was no major damage there.

"It was a pretty strong ride here, a lot of shaking but nothing broken," Reed told The Associated Press in a phone interview from his home. "I've talked to a few people and we have no reports of injuries or damage. There was a lot of shaking, but it wasn't the big one."

NBC11.com Earthquake Interactive

Rod Foo, a resident of south San Jose, about 10 miles from the epicenter, said everything in his house shook for several seconds, but the electricity never went out and his telephone was still working.

"I could hear it coming up the street before it hit the house," said Foo, a former reporter with the San Jose Mercury News. "I thought it was the kids messing around at first, then I felt the house shaking and I knew it was an earthquake. ... It was rattling for a long time and really loud."

Allison Guimard, 25, a technology executive who lives in Mountain View, about 18 miles west of the epicenter, said her fine China dishes started shaking and she grabbed her dog. It was the first significant earthquake for her and her husband, Pierre, who moved here from New York six months ago.

See Who Felt It

"It felt like the apartment was rolling -- shaking and rolling," said Pierre Guimard, 25, a home entertainment installer. "Almost like a boat on the water."

A woman who lives in the Santa Teresa area, near Oakridge Mall said it shook her house. She said it felt like a sledgehammer slammed into the house at least four times.

That house had many frames on the wall that swayed and were left askew, but no damage.

The woman also said the water in her swimming pool was moving so much that it had a wake.

There were also reported of burst water pipes and some cracks in the walls in south San Jose.

Pacific Gas and Electric told NBC11 there were no power outages associated to the earthquake.

An NBC11 viewer from Manteca said they felt like someone kicked the back of their couch and their fireplace tools started swaying.

Their daughter in Stockton said her furniture actually moved with her in it by the shaking.

The last major earthquake in Northern California -- a magnitude-7.1 -- struck in October 1989 just before the third game of the World Series at Candlestick Park. The quake, centered in the Santa Cruz Mountains on the San Andreas fault, killed 62 people and caused nearly $3 billion in damage.

Aaron McLear, a spokesman for Gov. Arnold Schwarzenegger, said the state would "will review and inspect all important infrastructure," including levees in the coming days.

Earthquakes powerful enough to be felt through the Central Valley have been of increasing concern since Hurricane Katrina because of their potential to weaken the earthen levees that channel rivers throughout the Sacramento-San Joaquin Delta.

A San Jose State volleyball game against Pacific was postponed due to the earthquake.

The school put out a news release that said just as Niki Clement put away her team-high 11th kill, the ground started to shake in Spartan Gym.

After the earthquake rattled the two teams, spectators and officials, a decision was made to postpone the San Jose State-Pacific volleyball match with the Spartans leading 26-25 in game two. San Jose State won game one 30-26.

Bay Area Rapid Transit trains were stopped for five minutes after the quake occurred, said BART spokesman Linton Johnson. Standard protocol for BART trains is to have the operators start running the trains again but only at half speed.

The operators will drive slowly while looking out the window for damage on the tracks, said Johnson.

Fire stations in San Francisco manually rolled up their garage doors as a precaution, NBC11 reported.