A pregnant teenager and her husband who died after their car smashed into a coach following a police pursuit were not present at the time of the burglary that prompted the officers’ response, investigators said.
Newlyweds Patrick McDonagh, 19, and his 18-year-old wife Shauna, were killed on the A40 near East Acton in west London at about 9pm on Sunday.
The car they were in was on the wrong side of the road when they died in a head-on collision with the coach.
A second man who was travelling in the car was taken to hospital.
Around 20 minutes earlier police had been called to reports of an aggravated burglary in Harrow and began a road chase.
The Independent Office for Police Conduct (IOPC) has said it is understood that police were pursuing the car, a Renault Scenic, for about 10 minutes but terminated the pursuit prior to the crash.
An IOPC statement said: “It has now been confirmed, as part of a separate police investigation, that the occupants of the Renault were not present at the time of an aggravated burglary reported to have taken place in Harrow.”
The IOPC said its investigation would look at “the information the police had and the rationale for the pursuit”.
A National Police Air Service helicopter was tracking the Renault when it crashed.
Accounts from officers, along with footage from the helicopter, police cars, body-worn video, CCTV and in-car data are among the evidence being gathered by investigators.
The Metropolitan Police made a mandatory referral to the IOPC later on Sunday.
IOPC regional director Jonathan Green said: “My thoughts are with the families and friends of Patrick and Shauna, those injured and all those affected by this incident.
“It is important that we now establish all of the circumstances surrounding this collision.
“We have therefore launched an independent investigation into the events leading to the collision and immediately deployed our investigators to attend the scene and the post-incident procedure.”