Image caption Whitehall is blocked by police, but life goes on outside the cordon

"We are going to do work as usual. We are not going to let it get us down. The security services have done an amazing job. We can put our trust in them I think."

Eric Lomas summed up the feelings of many Londoners in the aftermath of Wednesday's attack on Parliament, which left four people, including a police officer and the attacker, dead.

After the initial shock and confusion when news of the attack broke, and the text messages from loved ones asking if they were OK, the mood quickly settled into one of quiet defiance.

"To be honest, all of us have been expecting something of this sort," said Mr Lomas, who works in Parliament Street, which was inside the police cordon on Wednesday.

"We've just been wondering what form it might take. Luckily the injuries and deaths are much smaller than it would have been with a major explosion, but we still feel very sorry for those who are affected by it. We are always on our guard though."

Watching commuters stream out of Charing Cross station, next to Trafalgar Square, it felt like the hectic rhythm of London life had barely been interrupted.

The only real difference was the empty streets around Parliament and the heavy police presence at road junctions.

Cyclists had The Mall and the other broad avenues around Parliament to themselves, and the flags on government buildings were flying at half-mast.

Image caption Scientist David Fowler is in London for business meetings

"I've already seen a number of police officers who are armed, around this area, so I don't feel unsafe," said a young Lithuanian women, with a near-flawless English accent.

"Yesterday morning when I came into work there was nobody there - but this morning there are police officers standing by each of the traffic lights so it's noticeably a lot more.

"I feel more confident. If something happened, they would be there to help out and make sure the right support is provided for people."

Image caption Rhian Medi Roberts with two-year-old son Owain

David Fowler, an air pollution scientist, down from Edinburgh for business meetings, said he planned to "carry on as exactly as normal".

It was business as usual in the Houses of Parliament too, despite the surrounding roads still being cordoned off by police.

Staff and MPs were being allowed through to get to their offices.

Rhian Medi Roberts, an aide to Plaid Cymru MP Hywell Williams, was on her way to work as normal, with two-year-old son Owain.

Like other working mothers who use the parliamentary creche, she found herself in lockdown on Wednesday and unable to collect her child.

"We were both locked in until 19:30. We had a crowd with us in our office. The nursery staff were amazing. They kept us informed via email. And if it goes post-18:00, the chef will prepare them tea. So they all had homemade pizza. They were fine."

She said she had thought about not coming in to work but added: "I've just got things to do. You've got to carry on haven't you?

"It's a bit of a hassle, but two men carried the pram up the stairs at St James's station. People have been very kind, so I think you have just got to carry on."

Image caption Cyclists had The Mall to themselves

Image caption Flags are at half-mast across Westminster

Labour MP Stephen Timms, who in 2010 was badly injured by a man wielding a samurai sword at his constituency surgery in east London, said: "The mood this morning is restrained.

"There is a little bit of difficulty getting in and out of the building at the moment but otherwise completely calm."

He added: "I am expecting today to be business as usual. We are determined that it should be as normal as possible."

The central lobby between the two Houses, normally a hive of activity, and Westminster Hall, the cavernous mediaeval building, which on Wednesday was packed with journalists and MPs evacuated from their offices, were deserted apart from armed police and a gaggle of staff from the parliamentary gift shop being briefed by their boss.

The adjacent New Palace Yard, where the attack happened, was eerily quiet, with red police tape flapping in the breeze and an ambulance with its doors open next to a empty stretcher.

But there were soon familiar faces, including Labour leader Jeremy Corbyn, striding past the crime scene en route to the chamber for a minute's silence.

Image copyright Conservative MP Image caption Steve Baker: "We are not going to be cowed by terrorists"

Conservative MP Steve Baker said: "The mood amongst MPs is exceptionally sombre. I think we are very conscious that there are seven critically injured people out there. That people lay dead, including a police officer, whose job here is to defend us, which he has done.

"We all know that this is a target under a severe terrorist attack and I think many of us always expected that at some point there would be an attack and we are grateful the police have looked after us.

"We are not going to be cowed by terrorists. We are going to continue to operate our democracy in the normal way. They are cowards and we are absolutely never going to give in to them."