Byline: Ted Poe 

The FBI has issued warnings to the U.S. military and law enforcement groups that they are being targeted by terrorists, says Rep. Ted Poe, chairman of the House Subcommittee on Terrorism.

"There is an FBI bulletin warning for law enforcement and military to be concerned," Poe, a Texas Republican, said Thursday on the "Steve Malzberg Show" on Newsmax TV.

"Our law enforcement follows the chatter on social media of these radical groups and keeps up with them to some extent that way. These individuals have been targeting U.S. military personnel.

"They've been alerted in the U.S., and law enforcement as well, that they may be targets. If a person is actually determined to do that, it's very difficult to stop that."

Poe, who is also vice chairman of the House Subcommittee on Immigration and Border Security, revealed the warning a day after an attack on the Canadian parliament by a lone gunman left one soldier dead.

Poe said legal ports of entry between the U.S. and Canada have increased their scrutiny of those crossing the border.

"They're just doing a more thorough job of checking," said Poe, who believes the attack in Canada raises new red flags on how secure the American borders are from terrorists.

"The northern and southern borders are still porous. People who want to come into the U.S. unlawfully and illegally can cross through the southern border easier than the northern border," he said.

"But there are places in the northern border where it seems to me it's more porous than it certainly ought to be."

Poe agrees with the immigration rules followed by both the United States and Canada in that a person considered likely to radicalize and join a terror group is not permitted to leave the country.

"Their passports are held so they can't leave. That's probably the best way to handle that. They go overseas and then they're going to be joining ISIS somewhere to cause harm," he said.

But those that do leave and join terror groups must then be prevented them from coming back into the country as well.

"The FBI handles those on an individual basis to see where they can watch them the closest," Poe said.