STOCKTON, Calif — UPDATE: 8:45 a.m.

PG&E officials confirmed to ABC10 that a gas leak in Livermore shutdown all ACE trains going to San Jose from Stockton.

Investigators with the utility company are on scene near 4671 Las Colinas Road searching for the source of the leak. Officials said they are monitoring the air quality, but confirmed there is no immediate harm to the area.

According to ACE Train officials, trains are expected to be running as normal on Friday.

This is a developing story. We will have more information as it becomes available.

UPDATE: 7:00 a.m

ACE Trains connecting Stockton to San Jose were canceled Thursday after PG&E received overnight reports of a possible gas leak, the utility company confirmed to ABC10.

According to PG&E, a contractor notified gas officials of the possible leak in the Livermore area, but the utility company said it cannot yet confirm there is one.

After being alerted to the possible leak, ACE Trains said it shutdown "out of an abundance of safety."

This is a developing story. We will have more information as it becomes available.

ORIGINAL POST:

All Altimont Corridor Express Trains connecting the Central Valley to the Bay Area have been canceled Thursday because of a "major gas leak," officials confirmed to ABC10.

According to ACE Train officials, the gas leak is in the Livermore area, which is the fourth stop coming from Stockton. It's unclear how long the gas leak will cancel trains.

The first train out of Stockton to San Jose was scheduled to leave at 4:20 a.m.

Livemore Police Department confirmed to ABC10 that there is a gas leak in the area, but "the gas company" is working on a fix. Police officials could not say which gas company it was. PG&E could not be reached for comment.

The utility company's website shows there are currently no widespread gas leaks.

ACE Trains website early Thursday morning showed that there was a more-than 40 minute delay for trains headed out of Stockton, but officials confirmed to ABC10 that all trains are canceled, not delayed. The website was later updated to reflect "No trains are currently running."

More than 28,000 people in Stockton are considered super commuters, traveling daily from the city to the Bay Area.

This is a developing story. We will have more information as it becomes available.