The mother of a Chelmsford man shot dead during a chance confrontation outside a petrol station has said she is “heartbroken” as a 16-year-old boy is questioned over his murder by Essex Police.

East Anglian Daily Times: John Pordage. Picture: CONTRIBUTEDJohn Pordage. Picture: CONTRIBUTED (Image: Archant)

John Pordage, from Galleywood, was gunned down outside a BP garage in central Chelmsford on Saturday morning.

The 34-year-old was stood near the petrol station, which is close to the Army and Navy flyover in Baddow Road, with his 25-year-old friend when a blue Ford Fiesta pulled up at around 2.10am.

Someone inside the car, who police believe the pair knew, got out to speak to them before the situation grew violent and Mr Pordage was shot in the chest.

On Sunday night, Essex Police said that a 16-year-old boy from Chelmsford had been arrested on suspicion of murder on Sunday evening. He was being held in custody for questioning on Sunday night.

East Anglian Daily Times: Forensic teams work at the scene of a shooting in Chelmsford. Picture: NIGEL BROWNForensic teams work at the scene of a shooting in Chelmsford. Picture: NIGEL BROWN (Image: Archant)

Three other people, including a boy, 15, who were arrested on suspicion of assisting an offender on Sunday afternoon, also remain in custody for questioning. They are: a 15-year-old boy from Chelmsford, a 22-year-old man from Chelmsford, and an 18-year-old man from the Billericay area.

• Sunday night update: Mother pays an emotional tribute to John Pordage.

The shooting happened outside the BP garage on Baddow Road

Detectives originally believed Mr Pordage was shot by an occupant of a blue Ford Focus but senior investigating officer Detective Chief Inspector Stephen Jennings said the suspect was not in a vehicle at the time of the shooting.

He left the scene in the car before police arrived and the victim, of Galleywood, was taken to hospital where he later died.

Police have recovered the car.

Mr Jennings, of the Kent and Essex Serious Crime Directorate, said: “My thoughts are with Mr Pordage’s family during this extremely difficult time and our inquiries are progressing into finding those responsible for his tragic death.

East Anglian Daily Times: Floral tributes to John Pordage have been left under the cordon. Picture: NIGE BROWN.Floral tributes to John Pordage have been left under the cordon. Picture: NIGE BROWN. (Image: Archant)

“We are continuing to keep an open mind about the motive behind this shocking incident.

“From our inquiries so far, we believe this was a chance meeting involving people known to each other.

“There was an exchange of words, which escalated into a violent disturbance during which Mr Pordage was shot.

“We have established that at the time of the incident, both he, his friend and the suspect were not inside any vehicles.”

East Anglian Daily Times: Forensic investigators at the scene of a fatal shooting at the BP garage in Baddow Road, Chelmsford. Picture: NIGEL BROWNForensic investigators at the scene of a fatal shooting at the BP garage in Baddow Road, Chelmsford. Picture: NIGEL BROWN (Image: Archant)

He appealed for witnesses to come forward with any information. Call 101 to help.

The road was closed for forensic examination and patrols in the area had been increased, the force said.

Police patrols have been stepped up in the area in the wake of the shooting.

Neighbours said they were shocked to hear what had happened, but Superintendent Steve Johnson, earlier on Sunday before the family tribute and news of the arrests, reassured people that police do not believe there is any wider risk to the public.

East Anglian Daily Times: A murder investigation was launched when Mr Pordage died in hospital after being shot in the chest. Picture: NIGEL BROWNA murder investigation was launched when Mr Pordage died in hospital after being shot in the chest. Picture: NIGEL BROWN (Image: Archant)

He said: “Residents will have seen extra police officers in Chelmsford this weekend.

“We do not believe there is a wider risk to the community but we will continue these extra patrols to provide reassurance to the community as the murder investigation continues.

“As well as providing reassurance to members of the public, my officers will also deal with anyone intent on causing any trouble.

“Anyone who has concerns is encouraged to speak to our officers or call us.”

• Witnesses, those with mobile phone or dash cam footage and anyone with information should call 101.

Alternatively, contact Crimestoppers anonymously on 0800 555 111 or www.crimestoppers-uk.org.