Russia poisoned Skripal at home with nerve agent, say UK police

Police officers prepare equipment as inspectors from the Prohibition of Chemical Weapons (OPCW) begin work at the scene of the nerve agent attack on former Russian agent Sergei Skripal, in Salisbury, Britain March 21, 2018. REUTERS/Peter Nicholls.

The first contact with the nerve agent novichok for former Russian spy Sergei Skripal and his daughter was right at home, say British police -- literally at the front door.

"Specialists have identified the highest concentration of the nerve agent, to-date, as being on the front door of the address," London's Metropolitan Police said in a statement.

The Skripal residence in Britain was pinpointed as an initial attack site, UK authorities said on Wednesday, March 28.

A high-profile, international investigation into the attack continues, as do Russia's denials.