Forensic officers are searching a caravan site three miles from where a newlywed policeman died in the line of duty after being dragged by a vehicle as he responded to reports of a burglary.

PC Andrew Harper, who was due to go on honeymoon next week, was killed late on Thursday evening when he was struck by a vehicle after leaving his car at the crossroads on the A4 near Sulhamstead village, Berkshire.

Thames Valley police have launched a wide-ranging murder investigation into the 28-year-old officer’s death and have arrested 10 suspects, including a 13-year-old boy. All the suspects, the oldest of whom is 30, remain in custody.

The force has provided more details on the incident that led to Harper’s death while he was responding to a report of burglary at a residential property at 11:18pm. The officer on duty with Harper was not physically injured, but is receiving emotional support, police confirmed.

The family of PC Andrew Harper is releasing this image of him.



They kindly ask that their privacy is respected during this difficult time. pic.twitter.com/BRWbLVVARa — Thames Valley Police (@ThamesVP) August 17, 2019

On Saturday, forensic officers were seen scouring the caravan site on Padworth Road, near Burghfield Common, where two vans were apparently blocking the entrance. Inquiries are currently focusing on one vehicle, understood to be a Seat.

Thames Valley police would not comment on whether any of the suspects resided at the caravan site, but said: “This police presence forms part of the investigation following the death of PC Andrew Harper. Officers are at the scene making inquiries.”

The force also refused to comment on a report suggesting that Harper was hit by a second police car which was responding to the incident.

Meanwhile, Harper’s father, Philip, spoke of the family’s grief following his death. “We’re absolutely devastated and we’re in a bad place,” he said to Sky News.

Grieving colleagues also laid floral tributes at the scene of Harper’s death, with one describing him as “Thames Valley’s finest”. The officer had served as policeman for nearly a decade.

Another tribute read: “A shockingly sad day. We come together as a brotherhood at times like this and hopefully your family can take some comfort from that love and support.”

Police vans were blocking the entrance to the caravan site on Padworth Road as part of the investigation. Photograph: Ben Birchall/PA

On Friday, the Thames Valley chief constable, John Campbell, explained that Harper was at the scene with a fellow officer and was out of his police car when the incident occurred, adding: “What we do know is, Andrew had been dragged along by a vehicle.”

The suspects were detained within approximately an hour of the incident and officers were working “hard and diligently to find out what happened”, he added.

One witness told the Daily Mail that Harper’s colleague begged the officer to “stay with me, keep breathing” as he lay dying in the country lane.

Campbell said Harper was a “highly regarded, popular member of the team”, adding: “Everybody I’ve spoken to about Andrew talked about the incredible personality he was, what a fantastic police officer, and what a great friend and man he was, and he’ll be sorely missed by everybody.” The force’s flags are flying at half-mast as a sign of respect “in honour and memory of Andrew”, he said.

A postmortem examination is taking place to establish the cause of death. Harper joined as a special constable in 2010 before becoming a police officer a year later, serving in the roads policing proactive unit based at Abingdon police station.

Facebook pictures show Harper and his wife, Lissie, celebrating their wedding a month ago at Ardington House, a Georgian manor in Oxfordshire set in picturesque gardens and parkland.

Paying tribute, the deputy police and crime commissioner at Thames Valley police, Matthew Barber, said: “Talking to police who knew him well on the force, he [PC Harper] was a very popular officer.”

John Apter, chair of the Police Federation of England and Wales – which represents rank-and-file officers – called the death of 10 officers in the last decade “shocking”.

“Those figures are shocking for an unarmed force,” he told BBC Radio 4’s Today programme. “For 10 officers to be killed at the hands of others over that period of time is truly shocking.”