Officers seek information about 4x4 seen in Forest Gate where Corey Junior Davis, 14, was killed and a 17-year-old wounded

Detectives investigating a double shooting in east London which a 14-year-old boy was killed want to trace a vehicle seen leaving the scene.

Officers described the vehicle as a large, light-coloured 4x4 that was seen driving away immediately after the shooting in which Corey Junior Davis was killed and a 17-year-old boy was wounded.

“This is a very tragic incident. A teenage boy’s life has been taken in an extreme act of violence, leaving his family utterly devastated,” said DCI Dave Whellams of Scotland Yard’s murder squad.

Police said they were called to an estate in the Forest Gate area on Monday after reports that two people had been shot. The victims were taken to a nearby hospital and the younger boy, known as CJ, was pronounced dead on Tuesday.

The 17-year-old, who has not been named, was said to be in a stable condition but with potentially life-changing injuries.

Police said a postmortem examination would be held in due course and no arrests had been made.

CJ’s grandfather Neville McLeod said there was “nothing bad you could say about CJ”. “He was a lovely boy. He was just in the wrong place at the wrong time. He never kept bad company, so we just have no idea why this has happened,” McLeod told the London Evening Standard.

“I’m feeling devastated, the whole family is. These people don’t care, they go around with these weapons. I want to say to these people, stop it, where is it going to take them? Why do people have to go around carrying knives, guns, shooting and killing people? There’s no reason for it. Why do they have to do it? They act like life is cheap. CJ did nothing to deserve this.”

McLeod told Sky News his grandson had never been in serious trouble before. “He lives with me here and, every morning, he got up, had his breakfast, had his bath and he’d say: ‘Granddad, I’ll see you later.’ But he always came home. He never came home the other day.”

The incident happened outside a children’s playground at the entrance to a housing estate, residents said on Wednesday. They said the shots were fired from the direction of the road into the estate.

CJ, who police said was from the greater Forest Gate area, was shot and fell outside the entrance to the playground and lay by the stump of a tree that was enclosed by brickwork, according to residents. The older victim was also hit and ran away into the estate to hide, they said.

One woman, who did not want to be named, told the Guardian: “He ran round and behind the storage block. He was shot in the leg. He was trying to help the boy who died.”

Two bunches of lilies had been left near the spot where the older boy took refuge – one of few visible signs that anything had happened in the area, along with police tape used to cordon it off.

“I wouldn’t say this is a quiet area. It is proper London – it is busy,” the woman said.

The shootings happened around the corner from a secondary school of 1,200 pupils, including most of the children in the area, she added.

A man who lives nearby, who also asked not to be named, said he regularly saw the two boys in the place where the incident happened, but did not believe they lived on the estate.

He said he recognised the boy who was killed as one of a group who would come to the area regularly, the boy bringing his bike.

Another woman, who runs an estate agent and was born in the area, said she felt police were under-resourced and that more working security cameras needed to be installed.

Police said they were keeping an open mind about the motive for the shootings but they are not believed to be linked to a stabbing at the nearby Westfield shopping centre last week.

The local police commander, Ch Supt Ade Adelekan, called for an end to violence in the area after a string of recent shootings that are believed to be linked to each other, if not necessarily to Monday’s attack.

Whellams said: “We are working tirelessly to work through the evidence and piece together the events which led to Corey’s murder. I am specifically appealing for information about a large, light-coloured 4x4-type vehicle that was seen leaving the scene immediately after the shooting.

“Did you see this vehicle in and around the area of Moore Walk shortly after 3pm on Monday 4 September? If you did, please contact the incident room – any information could prove to be vital to progressing this investigation.

“I would also ask any members of the public who have footage or images of the incident or the events surrounding the incident to retain this footage and contact police.”

Anyone with information can contact police on 020 8345 3775 or 101 or Crimestoppers anonymously on 0800 555111.