Twelve people have been arrested by officers investigating the events leading up to the crash on the A66 which killed seven people, including two police officers.

Some of those held over the A66 investigation are suspected of “participating in the activities of an organised crime group” Cleveland Police said, adding that four of those killed in the car which hit the police vehicle had previous police convictions.

Police said nine men and three women, aged between 19 and 61, were arrested over alleged criminality leading up to the collision for offences include possession of a firearm and participating in the activities of an organised crime group.

The force said on the morning of the collision, it received several reports of two vehicles being driven dangerously.

The first vehicle, believed to be a Volvo XC60, was witnessed ramming properties in the Middlesbrough area.

The second vehicle, a Volkswagen Passat, is believed to have been associated with the activities of the Volvo.

Police said both vehicles were operating with cloned number plates but were picked up by automated number plate recognition technology.

The Volvo XC60 involved in the initial reports has been traced and recovered in Middlesbrough.

Pc Matthew Blades, 37, and Pc Tom Clough, 38, were killed when the Volkswagen Passat, that had been pursued by police and was driving the wrong way on a dual carriageway, hit their marked armed response vehicle.

Cole Robert Worthy, 17, Theo Rae, 17, Makai Saddington, 18, and 23-year-olds Michael Robert Cahill and Jacob Matusiak were also pronounced dead at the scene near Middlesbrough early on Saturday.

The crash in Teesside took place 10 seconds after a pursuit by other officers was terminated.

Four of the five people in the Passat, including three teenagers, had previous police convictions, Cleveland Police said.

More than £250,000 has been raised for their families.

A fundraiser created by the Cleveland Police Federation on Sunday reached £228,000 early on Monday.

Organisers said funds raised would be split equally between the two officers’ families and the federation would continue to provide support.

A second crowdfunder for the families had raised more than £27,600.

Family members described former Civil Nuclear Constabulary officer Pc Clough as “our hero” who was “always on public duty”.

The father-of-two’s family called him “our superhero” and said: “He gave his life in the line of duty, protecting and serving others with courage, dedication and selflessness.”

In a statement issued by Cleveland Police, Pc Blades’ wife called him “my beloved husband, my best friend, and the most devoted father to our two young boys”.

She said he was “an adored son and brother, a perfect son-in-law, and the most fun uncle”.

It has emerged the TikTok for one of the men that died, Makai Saddington, featured a string of videos appearing to show him in high-speed police chases.

Andy Burnham said people who share footage glorifying dangerous driving are “doing something that’s truly reprehensible”,

He made the comments on Monday during a visit to Kyiv as the Government urged TikTok and other social media firms to remove wrong-way driving videos.