LONG BEACH, Calif. -- In Cologne, Germany, authorities arrested a 29-year-old Tunisian man they say was planning an attack with the deadly toxin ricin. It's a biological weapon made from castor beans, and inhaling or ingesting just one milligram can be deadly.

In the U.S., authorities are trying to keep up with ever-changing terror threats, including possible attacks at sea.

From a hovering helicopter, a sniper takes out an enemy combatant, and an elite U.S. Coast Guard counter terrorism team swings into action, rappelling to the deck and taking command of the ship. CBS News rode along for the elaborate training exercise off the coast of southern California, where team members disguised as terrorists are mixing a deadly weapon to disperse on shore.

A 2017 Homeland Security bulletin specifically warns about terrorists wanting to use "poisons or toxins outside of conflict zones."

An elite Coast Guard team trains for a chemical weapons attack off the coast of California CBS News

In one drill, a participant disguised as a terrorist is wearing a protective suit, because of supposed chemical weapons on board. As the helicopters provide cover, boats deliver more of the Coast Guard's equivalent of special forces.

"Anything you can think of that's what the bad guys are thinking of as well so we prepare for any threat that's out there," said Capt. Dwight Collins, who commands the Maritime Security Response Team.

Once the entire team is on the ship, they go inside to try and "neutralize" the weapon, taking only a minute to do so.

"It's highly technical," Collins said. "They're taking samples of the agent and they are going to run tests on it to determine what they have."

A Coast Guard team trains to deal with chemical weapons CBS News

It can take up to two years of training just to qualify for the elite team. CBS News asked member Brian Mullinax, a 16-year Coast Guard veteran, if nerves ever get to him on the boat.

"Once we get out here and doing it, it's kind of adrenaline," he said. "This is our home and we're here to protect it. That's why we're here."

They train for everything. Roughly 13 million Americans are expected to take a cruise this year, and if a ship is taken by terrorists, the team responds. The threats are now such a concern that the Coast Guard activated a West Coast team earlier this year.