A man found shot dead in a car is believed to be a former imam at a London mosque known as an outspoken critic of the Assad regime in Syria.

Abdul Hadi Arwani is said to have been found in a car in Wembley, north London, yesterday morning.

Police were called to reports of a man suffering what were believed to be gunshot injuries to his chest at 11.15am.

They found a man in his late 40s sitting in a dark coloured Volkswagen Passat in Greenhill, at the junction with The Paddocks. He was pronounced dead at the scene around half an hour later. A post-mortem examination will be carried out.

Scotland Yard, which has not released the identity of the dead man, said detectives had an open mind about the possible motive of the shooting. Mr Arwani was born in Syria and was a former imam at the An-noor Masjid mosque in Acton, west London, according to reports.

He was said to have been an outspoken critic of President Bashar Assad and is believed to have attended protests against the regime outside the Syrian embassy in London in 2012.

Tributes to him were paid on social media.

One Facebook message said: “Our beloved sheikh Abdul Hadi was murdered this morning in Wembley whilst sitting in his parked car. Bullets found in him. This is no ordinary murder. We ask Allah to shed his mercy upon the sheikh.”

Another on Twitter read: “The Muslims in the UK have lost a great Imam and a person of knowledge. May Allah have mercy on you Sheikh Abdul Hadi Arwani.”

Mourners gathered at what is believed to be Mr Arwani’s family home in Acton last night. There was no answer at the door.

A man at the mosque said they would be making no comment. Mr Arwani graduated in Jordan and was an authority on Islamic marriage contracts and divorce law, according to the London College of Islamic Studies website.

The death is being investigated by detectives from the Metropolitan Police’s Homicide and Major Crime Command.

They appealed for anyone in the area from about 10am who may have seen a dark coloured VW Passat or anything suspicious to get in touch.