TWO more arrests have been made following the murder of PC David Phillips.

Two women - a 19-year-old and 34-year-old, both from Wallasey - were arrested on Tuesday night on suspicion of assisting an offender.

They are both being questioned at police stations on Merseyside today, Wednesday.

It comes less than 24 hours after two men were arrested on suspicion of the policeman's murder.

The pair aged 18 and 30 years from Oxton and Wallasey remain in police custody this morning.

34-year-old father-of-two PC Phillips was killed trying to stop burglars escaping in a red Mitsubishi they had taken from an estate agent in Birkenhead, in the early hours of Monday morning.

He died from internal injuries, a post-mortem examination found.

Sir Jon Murphy, chief constable of Merseyside, said the officer had been trying to use a stinger device to stop the car when it swerved on to the central reservation of Wallasey link road and mowed him down.

Officers have also executed four warrants in the Oxton and Wallasey areas as part of the investigation.

The arrests come as detectives continue to urge the public to come forward with information.

Sir Jon said officers understood the risks they faced, but added: “Their wives, their husbands, their loved ones and their families expect them to come home at the end of their watch.

“Sadly, David did not and his daughters will have to grow up without their father.”

Detective Chief Superintendent Paul Richardson, said: "I would like to thank the public for their overwhelming support. Since the investigation was launched yesterday we have been inundated with calls from members of the public  and as a result we are following up a number of positive lines of inquiry.

"From the hundreds of supporting and caring comments on social media and media websites yesterday it is obvious that there is overwhelming support for the police and that the public appreciate the work undertaken by officers like PC Phillips to keep their communities safe.

"I would like to appeal to any members of the public who have any information which could help us with the investigation to come forward.

"You may not think that the information you have will mean that much, but for us that information could be the vital piece of the jigsaw we need and is essential in helping us to build up a picture in relation to what happened on the night.”

Anyone with information should call the Matrix Serious Organised Crime team on 0800 230 0600, or Crimestoppers on 0800 555 111.