Transcript for UK Prime Minister Theresa May calls London Underground attack 'cowardly'

And punish thank you for doing this I know you've just met with your candidate Terry T and what's the latest on what happened. Yes we've had another terrorist attack in London on the ground and underground. College in the attack. And it was a device that was obviously intended. To cool significant home. 22 people. When Rangers. To that being treated in hospital none of this council's approval who in effect treating it as an act of terror right now in prison term was up and tweeting. This morning he said that those behind this were in the sites. A Scotland Yard is that true. Well I don't think it's hope and won't speculate on network is an ongoing investigation. The police and the security says his all. Doing. The work necessary to discover the full circumstances of this how would he attack that's taken place and want to define all those who are responsible. And we are threat level remains at severe. Donkeys to say is on emergency services were on the scene this attack. In immediately. And well today. Lot things of that professionalism bravery and the rest of the city has carried but you've said in the wake of these other attacks enough is enough. Things need to change its time for some even embarrassing. Conversations which you mean by that. Well it is necessary for us to milk as we on doing that Wetherell peace and security services have the full capabilities the powers that they need. Of course we review of any instant it takes place and we have had sat in number of terrorist attacks. In the UK's unit of powers they need. Well that the exercise is being done I've given the next two palace as my time in office. Went to humanize him secretary before I became prime minister. Given the next two pounds but we duke again but. Why does the issues that we really need to be addressing an all be raising this. When Klein the United Nations is the question that the use of the Internet. By terrorists. Four terrorist planning but also this youthful using it for the spread of extremism. I hate treat if propaganda that can insulation can inspire terrorists he can you companies like FaceBook and Google. To do more. We're talking to them about to ignore and indeed companies to come together they formed a global forum. To look at what they can do to be dealing with this much more quickly and and in a special and they do it amendment so we're working with the company's. President term policy tweeted this morning that the solution is a bigger tougher travel ban. That's an idea you've been against is it something you would reconsider. I think what is important is that we're able to have the power is two. Looking to people to identify people who may be. Wanting to cause this home and optional seem to corsets Tom. I'm to be able to take necessary action when people do. Was not asked happens here in the United Kingdom when I was ten secretary. I learned more extremist hate speeches like skiing hear what's been hate pictures from Cummings of the UK than any home secretary of pool.

This transcript has been automatically generated and may not be 100% accurate.