Forensic officers at the suspected firing point of a shooting at a garage forecourt on the Crumlin Road where a policeman was injured Picture Mal McCann.

THE 'IRA' has claimed responsibility for a gun attack on police at a garage service station in north Belfast on Sunday.

The republican group described the attack at a service station on the Crumlin Road as a "targeted" attempt to kill two officers.

One was wounded after he was hit up to three times in the arm as he and a colleague left the filling station shop at about 7.30pm.

As many as 10 shots are believed to have been fired. The officer, who underwent emergency surgery, is still receiving treatment for his injuries.

PSNI Chief Constable George Hamilton said a bullet-proof vest may have saved the officer's life.

The ambush is believed to have been mounted from a derelict site opposite the service station. It is believed an AK47 was used.

Using a recognised codeword, the 'IRA' said the attack was unconnected to the recent collapse of political institutions at Stormont but was a "continuation of activity".

In a statement the group said the attack had been "planned for several months" with the movements of police being monitored.

The scene of the shooting is close to Tennent Street Police Station. The group said officers often used the service station.

"They had been using the service station regularly but there was never a pattern established," it said.

The group denied claims that the garage forecourt was sprayed by gunfire and said that the shots were concentrated on a ramp at a shop entrance.

Police forensic officers were back at the scene on Tuesday on the Crumlin Road, cutting down shrubbery and carrying out fingerprint searches of a nearby car park.

The area from which the shots are believed to have been fired remained sealed off yesterday as crime scene investigators continued to carry out an examination and take photographs.

Police believe the gunman may have taken cover in the car park and used it as a vantage point to launch the attack.

The dissident group has carried out similar attacks using automatic weapons in the past.

In 2013 shots were fired at police vehicles as they drove past nearby Ardoyne.

In November 2015 a gunman used an AK47 to fire upon a stationary police car in the Rosnareen area of west Belfast. No-one was injured in either attack.

Meanwhile 36-year-old Matt Johnston, who was arrested on Sunday evening following the gun attack, was released unconditionally on Tuesday night.

A solicitor for the north Belfast republican, who has previously complained about being harassed by police, accused the PSNI on Tuesday night of "cynical policing" and said he was considering legal options.

In a statement Madden and Finucane accused police of detaining their client "for nearly 48 hours without a shred of evidence being put to him in what appears to be an example of cynical policing".

It added: "Mr Johnston is considering his legal options available for scrutinising the lawfulness of his arrest and subsequent detention."

A 39-year-old man arrested on Monday following searches in west and north Belfast was also released unconditionally on Tuesday night.

A 30-year-old man remains in custody.

Police believe a red Audi found burnt out in Culmore Gardens in Andersonstown west Belfast at about 8pm on Sunday was used as the getaway car.

Detectives have appealed for information about its movements.

In a separate appeal on social media last night police in north Belfast appealed for help in tracking down those responsible.

Describing recent days as "difficult and busy" the Facebook post said that police would "carry on" despite the attack adding: "If you know anything or have any information, photos or camera footage of what happened we need to here from you phone us on 101."