LONDON, ENGLAND - SEPTEMBER 16: Police vans sit parked outside Portcullis House in Westminster on September 16, 2017 in London, England. An 18-year-old man has been arrested in Dover in connection with yesterday's terror attack on Parsons Green station in which 30 people were injured. The UK terror threat level has been raised to 'critical'. (Photo by Jack Taylor/Getty Images)
Police: Second man arrested in London attack
01:22 - Source: CNN
London CNN  — 

Anti-terror police in the UK are continuing to question suspects recently arrested on suspicion of attempting to blow up a London Underground train.

An 18-year-old man and a 21-year-old were arrested separately by police on Saturday, a day after the incident, according to UK police.

Police announced Tuesday the arrest of a 25-year-old man in Wales. There also were searches at four addresses, Metropolitan Police said.

The first two men arrested had been fostered by the same elderly couple, and at least one was a refugee from Iraq, local officials told CNN on Monday.

The 18-year-old was arrested by police in the departure lounge of Dover ferry port, which is the busiest ferry hub in Europe and a gateway to the French coast, police said.

The second man was picked up by police at a fast food carryout restaurant, Aladdin’s, in East Hounslow, a west London suburb on the way to Heathrow Airport, at about 11:50 p.m. on Saturday, police confirmed.

The co-owner of Aladdin’s named the man arrested as Yahya Farroukh, a Syrian national.

Suleman Sarwar said Farroukh had worked in the shop for a number of months and seemed normal.

“Normal. Just like how you get along with your colleagues. Very normal. If he did do anything, you would never suspect it,” he said.

“All we know is that he was arrested Saturday night and then the police came last night,” Sarwar told CNN. “The police didn’t tell us anything about the investigation. They gave no details out. They’ve just done a search. They searched lockers and that was it. It was closed for four hours and then the police went.”

Police have not released the names of either suspect.

Local council leader Ian Harvey told CNN the 18-year-old suspect was fostered by an elderly couple, Ronald and Penelope Jones, and was living with them at the time of the attack during rush hour Friday morning.

He said local residents had told him the teen was an Iraqi asylum seeker who had come to the United Kingdom three years ago after his parents were killed in Iraq. Harvey described the teenager as unhappy.

A local official said the second suspect had also been fostered by the Joneses. That source asked not to be named because he was not authorized to release the information.

Couple honored by Queen for fostering children

Queen Elizabeth II honored Ronald and Penelope Jones for their fostering work in 2010, awarding them MBEs (Member of the Order of the British Empire) “for services to children and families.”

Alison Griffiths, another local official, described the Joneses as “the sort of people who would never turn a child away, no matter what the circumstances.”

Griffiths, a Surrey County councillor, said the Joneses had fostered over 280 children in 30 years.

They have fostered about eight refugees in the past year, including children from Afghanistan and Iraq, she said.

“This has come as a big shock to them. You don’t expect it in your own house,” she said of the Tube bombing, which injured 30 people at Parsons Green station in west London on Friday.

Emergency services secure the area around Parsons Green station after Friday's explosion.

Police were continuing Monday to search their house in Sunbury-on-Thames, Surrey, on the outskirts of west London, PA reported.

“We can confirm that a search is taking place at a residential address in Stanwell, in connection with the arrest in Hounslow,” Surrey police said in a statement.

British TV showed images of the house as backing right on to the runway of Heathrow Airport.

Assistant Commissioner Mark Rowley, national lead for counter terrorism policing, announced Sunday evening the second arrest and said that the police were lowering the threat the UK was under from international terrorism from critical to severe.

Related: The unlikely suburban backdrop to London’s latest terror attack

ISIS claim

Shortly after the explosion, ISIS claimed involvement via its Amaq News Agency.

But when asked if ISIS may have had a hand in the attack, UK Home Secretary Amber Rudd said: “It is inevitable that so-called Islamic State or Daesh will reach in and try and claim responsibility. We have no evidence to suggest that yet.”

Rudd said the government is releasing an additional £24 million ($32.6 million) for counter-terrorism operations around the country, “particularly to support operations where they are protecting people in public places.”

Related: Britain’s terror challenge will last a generation

CNN’s Hilary Clarke, Richard Allen Greene and Lauren Said-Moorhouse reported from London, with Susannah Cullinane reporting from Auckland, New Zealand. CNN’s Jamie Gray, Carol Jordan, Stephanie Halasz and Lorenzo D’Agostino also contributed to this report.