The Los Angeles Police Department today urged Southlanders to remain vigilant about passing on possible terrorist-related information to authorities.

The plea was made in the wake of last week's discovery of packages containing explosive materials that were shipped from Yemen and addressed to religious sites in Chicago.

Security was beefed up at airports across the country, and security officials at Los Angeles International Airport convened an emergency meeting on Friday morning.

The suspicious packages shipped via UPS and FedEx were found Thursday night in England and Dubai, addressed to synagogues or Jewish centers in Chicago.

LAPD Cmdr. Blake Chow, assistant commanding officer of the Counterterrorism and Special Operations Bureau, said the LAPD has community outreach programs in place in the Jewish and Muslim communities, and is able to quickly communicate with key people and groups.

"Our outreach program -- the two-way communication between the LAPD and the community -- is one of the key linchpins in keeping the communities safe,' Chow said.

"We're able to take those contacts, and pass information on about we're getting from Washington; information that is accurate,' Chow said.

Chow said law enforcement liaisons have been communicating with security organizations representing "critical infrastructures' by using the Regional Public and Private Infrastructure Collaboration System -- RPPICS -- which is a secure computer system.

"The LAPD has been on top of what's been going on,' Chow said. "We take the information, analyze it and keep our community partners informed.'

Chow noted that the LAPD's iWatch program is in effect for people to report "suspicious behaviors and activities" to police.

"The iWatch system is huge,' Chow said, "because people have to have an easy way to communicate information to us. And the information flow in both directions is the key.'

People can pass along information to authorities by logging onto www.iWatchLA.org ; by calling (877) A-THREAT; by calling their local law enforcement agency; or by calling 911.