The eight injured were taken to hospital; two people were treated at the scene for minor injuries, police said in a statement issued on Sunday night.
The 48-year-old male driver of the van "was found detained by members of the public at the scene and then arrested by police," the police statement said.
"He has been taken to hospital as a precaution, and will be taken into custody once discharged. He will also be subject of a mental health assessment in due course," it added.
“Due to the nature of this incident extra policing resources have been deployed in order to reassure communities, especially those observing Ramadan,” police said in the statement.
Attack is violent manifestation of Islamophobia
The Muslim Council of Britain in a statement condemned the incident, adding that the perpetrator was “motivated by Islamophobia.”
The statement said witness accounts described the van “intentionally plowed into a group of worshipers who were already tending to someone who had been taken ill."
“During the night, ordinary British citizens were set upon while they were going about their lives, completing their night worship. My prayers are with the victims and their families. It appears from eye witness accounts that the perpetrator was motivated by Islamophobia,” said Harun Khan, the secretary general of the Muslim Council of Britain.
"Over the past weeks and months, Muslims have endured many incidents of Islamophobia, and this is the most violent manifestation to date," he added.
"Given we are approaching the end of the month of Ramadan and the celebration of Eid with many Muslims going to local mosques, we expect the authorities to increase security outside mosques as a matter of urgency," Khan said.
He further said that Muslims have been have been very concerned about "the growth in hate crime for many years and transformative action must now be taken to tackle not only this incident but the hugely worrying growth in Islamophobia."