>> Police efforts focused on a deadly militant attack in London Saturday night. Authorities say at least six people were killed as well as three attackers in what officials are calling an act of terror. Police say they believe there were no additional attackers beyond the three, who were shot and killed by armed officers.
Three major London hospitals are now on lockdown to keep patients and staff safe. They say at least 30 people were taken in by ambulance for injuries. Reuters Jacob Greaves reports from near the site of the incident.>> Details are still emerging, the area behind me has been cordoned off.
This is an ongoing police operation. What we know so far is on Saturday evening police were called after reports of a van threatening pedestrians and passersby on the London Bridge. Shortly after that, emergency services called after reports of stabbings taking place in nearby Borough market.>> Officials say armed units responded within minutes of the first emergency call.
Police said the attackers wore what looked like explosive vests which were apparently hoaxes. There have also been reports of a loud bang and gunshots. Dozens of people caught in the attack in the area were later escorted through a police cordon, some witnesses describing what they saw.>> And how many people did you see them stab?
>> They didn't know, three, maybe more, I think more than five.>> No, they don't care, just so you stand up, the police was in front, and they watched them stand up too, to do it, just do it.>> But they surrendered, they submitted.>> No, no no.
>> They fought the police?>> Yeah.>> Islamic State sent out a call earlier on Saturday to its followers to launch attacks during the Muslim holy month of Ramadan. Saturday's chaos echoes a March attack on Westminster Bridge, where a man killed five people after driving into a crowd of pedestrians before stabbing a police officer.
And it came just two weeks after suicide bomber Salman Abedi blew himself up at an Ariana Grande concert in Manchester, killing 22 people. London's Thames River Police said it was working with life boat rescue to locate any people that had jumped away from the attack on the bridge.
U.S President Donald Trump fired off a tweet amid the deadly drama, offering U.S help to Britain and to promote his controversial travel ban as extra security for Americans.