Mother of two Lisa Smith has been named by police as the woman shot dead in Knockholt on Friday.
A man, who is said to have close relations to the victim is believed to be missing, with police investigating whether he later entered the River Thames after the incident.
A firearm was found in a vehicle on the Dartford crossing on the evening of the shooting which police have closely linked to main suspect, Edward stocking.
A few hours later call handlers received a reports of a man on the wrong side of the barrier Thames water. The search in the water continues.
The Three Horeshoes pub, in Knockholt where the shooting took place commemorated Smith with flowers and balloon tributes on the weekend after the shooting.