Armed police swooped on an east London mosque after a "masked" gunman entered the building during Ramadan prayers before shooting his weapon outside.

Worshippers at the Seven Kings Mosque in Ilford were part-way through evening prayers late on Thursday when the sound of a gunshot rang out.

A man, said to have had his face covered, was reported to have entered the mosque but was chased out by people inside before he fired the gun.

Scotland Yard said early investigations suggested that a "blank firing handgun" had been discharged. No injuries or damage to the building were reported and detectives were not treating the incident as terrorism-related, the force said.

No arrests have been made.

Worshipper Ibraheem Hussain, 19, described hearing the gunshot around half an hour after prayers began.

He said: "There's three sections of the mosque and at taraweeh (evening prayers) during this time of Ramadan the mosque is packed out.

"We were upstairs in the classrooms and about 30 minutes into the night prayer a large noise went off.

"I just continued my prayer, it sounded like a firework or maybe something heavy had been dropped, so no-one really thought anything of it.

"After we finished we were leaving the shoe area and someone said it was a gunshot, someone had come into the mosque and he had a firearm on him.

"The managers had seen him, he was masked and acting suspicious and the firearm was let off."

The incident comes amid heightened concerns over security at places of worship around the world following recent attacks in New Zealand, Sri Lanka and the US.

Mr Hussain, an apprentice data analyst at one of the Big Four city firms, said the incident left him concerned over the safety of worshippers during Ramadan.

"The main thing that was in my mind was that (due to the layout of the mosque) it could have gone very wrong," he said.

"(Christchurch) comes to mind, it's crazy to think this would happen in London, especially after everything that has happened.

"Another thing that is quite worrying is that the guy was on foot, so he could be in the surrounding area still.

"A lot of people - loads and loads of Muslims - were in that area in traditional garments so they could be targets, although we don't know what the aim was."

A diverse range of male worshippers use the mosque, including men of Pakistani, Bangladeshi, Indian and North African heritage, he said.

Following the incident the mosque's imam urged people not to speculate over the gunman's motives.

"There was a firearm incident outside Seven Kings Mosque tonight during Ramadan night prayers," Mufti Suhail said.

"The suspect ran from the scene when stopped by brothers standing guard at the mosque.

"A shot was fired which fortunately did not hit anyone."

Ilford North MP Wes Streeting said he would be contacting the police about the incident.

"I am aware of the reports of a man with a firearm at Seven Kings Mosque during prayers tonight and am relieved that no one appears to have been hurt or injured. Thank you to @MPSRedbridge for a swift response," he tweeted.

Scotland Yard said the investigation was being led by detectives from the East Area Command Unit, although the Trident gang squad had been notified.

"Police were called at 10.45pm on Thursday, 9 May to reports that a man, believed to be in possession of a firearm, had entered a mosque on High Road in Seven Kings," the force said.

"The man was ushered outside of the building by those inside. A gunshot was then heard.

"Officers, including firearms officers, attended. There were no reported injuries or damage to the building.

"At this early stage, ballistic evidence recovered from the scene suggests that the weapon was a blank firing handgun.

"Officers will continue to work closely with representatives from the mosque and are providing reassurance to the local community."

Last month nearly 260 people died in the Easter Sunday attacks in Sri Lanka, which included suicide bombings on several churches and hotels.

In March a mass shooting by a far-right terrorist at a mosque in Christchurch, New Zealand, left 50 people dead.

One woman was killed when a gunman opened fire at a synagogue in California in April.

In June 2017 one man was killed and nine other people were injured when far-right extremist Darren Osborne drove a van at worshippers near Finsbury Park mosque in north London.

Additional reporting by PA