Intensified security measures are being put in place on commuter rail lines, bridges and major transportation hubs following the latest military offensive against the Islamic State and other terror groups, the governors of New York and New Jersey said Wednesday.

In a joint announcement, Gov. Andrew Cuomo and Gov. Chris Christie said they were taking immediate steps to gird the region's infrastructure and indicated they could take additional measures in 30 days. They also agreed to increased collaboration amongNew York and New Jersey state agencies, the NYPD and federal officials.In New York State, the National Guard was doubling the number of soldiers to as many as 500 to patrol rail hubs and station platforms. Officials in New Jersey also said they were increasing uniformed officers at critical infrastructure points and putting additional marine and aviation units in place around bridges and mass transit facilities.

Increased baggage checks will also occur, as well as vehicle checks at bridge crossings, officials said.

Both Cuomo and Christie, as well as various law enforcement officials stressed at a Manhattan news conference that there is no known credible terror threat to either state in light of the bombing by the United States and its allies against the terror groups in Syria and Iraq.

Ten days ago they had both called for law enforcement officials in both states to review counter terrorism strategies. Yesterday's announcement was the result of that study.

"We cannot ignore these increased tensions even without a specific threat," Christie said. "We will continue to monitor this very closely over the next 30 days."

"There is no doubt these are very serious times," Cuomo said. "It is also undeniable that this region is a potential target for retaliation -- we know that."

They also will explore giving limited reciprocal authority for law enforcement officials in each state to act in each other's transportation jurisdiction.

Law enforcement officials in both states also agreed to plan tabletop exercises within the next three months, and a full blown field exercise in four months to test preparedness for a potential terrorist incident.

"That shouldn't raise anxiety," said Cuomo of the increased measures. "If anything it should have a calming effect, to say we are prepared and we are getting ready ... better safe than sorry."