Detectives have been given more time to quiz the suspect in the alleged terror attack outside the Houses of Parliament.

Salih Khater, 29, was arrested by armed police after allegedly ploughing into cyclists and pedestrians in the silver Ford Fiesta he was driving before crashing into a security barrier.

The British national, who is originally from Sudan, was originally held on a terrorism charge, but later further arrested for attempted murder.

He remains in custody at a south London police station and Scotland Yard said the force was granted a warrant to detain him until Monday August 20 at Westminster Magistrates’ Court on Wednesday.

His brother, Abdullah Khater, told the BBC he was a “normal person” and that their family, who are originally from Darfur, were in a “state of shock”.

The Metropolitan Police’s counter-terror head Neil Basu said on Tuesday Khater was not co-operating, while the priority of the investigation team continues to be to understand the motivation.

Mr Basu said the force is treating it as a terrorist incident because of its apparently deliberate nature, the method used and the “iconic” location.

The force said officers have concluded searches at two addresses in Birmingham and one in Nottingham, and continue to search a third in Birmingham.

The Bunna Internet Cafe in Sparkbrook, Birmingham
The Bunna Internet Cafe in Sparkbrook, Birmingham (Aaron Chown/PA)

Among those to express their shock at Khater’s arrest was Anwar Mukhta, who said he has known the suspect for eight years.

He told ITV News the current narrative will be revealed to be a “lie”, adding: “It is an accident, it’s nothing to do with terrorists, it’s nothing to do with any organisation that tried to make an attack to any Government department.”

Residents who knew Khater have described him as a quiet man who frequently visited the Bunna Internet Cafe on Stratford Road in Birmingham.

One customer, who would only give his name as Adam, said he had been served coffee by Khater and that he was a polite and apparently humble man.

“I am still in shock. I’ve known him for about a year and he is a very, very good man,” he told the Press Association.

“I can’t see him doing anything stupid.

“He was polite, humble and he kept himself to himself. The whole community is upset. I can’t see it not being an accident – I couldn’t see him hurting a fly, never mind a human being.”

Ahmed Abdi, originally from Somalia, said Khater was regularly at the cafe, and was a “very quiet” man who “never spoke” and drove a small, old white car.

The 43-year-old, who recognised his image on the news, said he knew the man as Salih and had known him for around a year-and-a-half.

Westminster car crash
A police van outside Brinklow Tower in Highgate Street, Birmingham (Aaron Chown/PA)

A police search is thought to have taken place about a mile from the cafe, at a tower block in the Highgate area, where a plainclothes officer prevented reporters from entering the 10th-floor landing.

Khater was previously an accountancy student at Coventry University, a spokesman said, confirming he attended between September last year and May.

He added that Khater failed the first year of his course and his enrolment was terminated.

POLICE Westminster
(PA Graphics)

The Facebook page for a man called Salih Khater says he lives in Birmingham, works as a shop manager, and has studied at Sudan University of Science and Technology.

It has subsequently been disabled and is no longer publicly available on the social network.

Birmingham Central Mosque said members of the local community believed Khater may have travelled to London for an appointment to obtain a visa to travel to Sudan.

Trustee Nassar Mahmood said inquiries in the local Sudanese community suggested Khater did not worship at the mosque and had shown no signs of radicalisation.

Mr Mahmood said: “Like the rest of the community of the UK, the people of Birmingham and the Birmingham Central Mosque are surprised, shocked and saddened by the incident at Westminster. Our thoughts and prayers are with the people who have been injured.”

The silver Ford Fiesta used in the attack was driven from Birmingham to London late on Monday and spent almost five hours in the Tottenham Court Road area.

It was then driven around the Westminster area for more than 90 minutes before it crashed into a security barrier just before 7.40am on Tuesday.

Footage aired on BBC News showed the car’s approach towards Parliament, where it crossed into oncoming traffic and collided with cyclists before entering a small road and crashing into a security barrier.

Westminster car crash
A residential property on Peveril Street in Nottingham which was searched by police (Josh Payne/PA)

Three people sustained non life-threatening injuries. One man was treated at the scene while another man and a woman were taken to hospital but were discharged by Tuesday evening.

Images posted online showed a man wearing a black puffer jacket being led away in handcuffs from the car as armed police swarmed the scene.

There was nobody else in the vehicle and no weapons were found, police said.

Witnesses described an emotionless driver who ploughed through cyclists who “were thrown everywhere” in what they said appeared to be a deliberate act.

The Houses of Parliament are surrounded with security barriers of steel and concrete.

The measures were extended after the Westminster Bridge attack in March 2017 when Khalid Masood ploughed a car into crowds on Westminster Bridge, killing four people.

Masood abandoned his car then fatally stabbed unarmed Pc Keith Palmer before he was shot by armed police in a courtyard outside Parliament.

The terrorist threat against the UK is seen as unprecedented.

Emergency services attending Khalid Masood, top, and police officer Keith Palmer, bottom, outside the Palace of Westminster after Masood ploughed into pedestrians on Westminster Bridge
The 2017 Westminster Bridge attack left four people dead (Stefan Rousseau/PA)

The Prime Minister’s official spokesman said there were 676 live investigations being carried out by the security services and counter-terror police at the end of June, up from more than 500 in March.

Some 13 Islamist plots and four by far-right extremists have been foiled in the past 18 months, he added.

There are roughly 3,000 active “subjects of interest” at any one time, while there is a wider pool of more than 20,000 individuals who have featured in probes whose threat must be kept under review.