Transcript for US law enforcement stepping up security after London terror attack

Here in the U.S., the the department of homeland security is saying it's closely monitoring the the situation and warning any Americans in the uk to maintain security awareness. Pierre Thomas is in Washington with that part of the story. Pierre, how are American authorities responding to the London attack? Reporter: Paula, good morning. Homeland security officials say there's no specific threat to the us. Law enforcement officials in some major cities are stepping up security. In New York City, expect to see heavily armed tactical teams. The governor has directed police to step up patrols in high-profile locations. There is no specific threat. There's always concerned a copy cats in the immediate aftermath of an event like we saw in London. Of particular concern are the low-tech attacks involving knives and vehicles used to kill. There's been a steady spate of notices to warn law enforcement agencies to be aware of those attacks. Dan? We want to get you to weigh in on something we've been discuss tong set. There have been tensions between the U.S. And uk after the Manchester leaks. So, as far as you can tell, how are oou.s. Agencies working with their British koupt parts? Reporter: Dan, urks K officials had hard feelings over the release of those details and stopped sharing information with their American counterparts for a brief period. Ultimate lirks the job at hand wins out. Trying to find out as much as they can as fast as they can about the suspects is the priority. I expect the uk security services will absolutely take advantage of the enormous intelligence resources that the U.S. Has to offer. The so called special relationship in tact. Pierre Thomas, thank you. This attack comes at the

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