A toddler was shot with an air rifle while playing with her family in a park in Feltham, according to police.
The three-year-old girl was left bleeding after the shot was fired in Hanworth Park on Thursday August 20.
She underwent surgery to remove the pellet from her stomach and spent two days recovering in hospital, officers added.
It is believed she had been running from her mother to her grandfather when a loud noise sounded and seconds later the she burst into tears, police said.
The horrific incident took place between 6pm and 6.15pm, and officers were called by the hospital staff after the little girl was admitted with a wound to her abdomen caused by an air weapon.
Detectives in Hounslow are appealing for anyone who may have seen or heard anything to come forward and help track down the shooter.
Detective Helen Larson said: "This was a horrific incident and we are appealing for anyone with information to contact police.
"This shooting could have been far worse, possibly fatal and we need to find the person or persons responsible.
"The little girl had to spend two days in hospital following surgery to remove the pellet.
"She has now been released from hospital and is making a good recovery and her parents have told us she is well in herself.
"She will need a number of follow up appointments at the hospital in the coming weeks.
"We have trawled CCTV and conducted searches of the area but thus far have not found any leads which may help us identify who was responsible.
"We do know a group of boys were seen to run out of the bushes nearby following the incident."
If you have any information please contact Detective Constable Helen Larson at Hounslow CID on 020 8247 6160 or 101 or report any information anonymously by calling Crimestoppers on 0800 555 111.
