Hertfordshire Police said in a statement that it was:

In February 2011, Song had his car impounded by Hertfordshire Police after he was caught speeding and failed to provide relevant documentation.

During the robbery, he shot and killed police constable Frank Mason of the Hertfordshire Police.

The local police force, Hertfordshire Police are in talks with the Home Office about a grant for "unexpected or exceptional costs".

Lillian Pilcher - Police staff, Hertfordshire Police.

Chief Superintendent Al Thomas of the Hertfordshire Police said, "We share the concern and sense of shock within the community.

All housemates were removed for their own safety while Hertfordshire Police carried out a thorough search of the premises at around 1:15am.

Hertfordshire Police have denied making any such warning and stated that the law allows householders the proportionate use of force to protect themselves.

Hertfordshire Police are leading the hunt for Clarke following the murder of Paul Milburn on April 26 in St Albans.

Anyone who can help Hertfordshire Police is asked to contact or Merseyside Police on.