A cyclist shot at a car in the first of two shootings in two days in a County Durham town.
The man fired two shots at a car in Windlestone Road, Billingham, on Tuesday before riding away.
On Wednesday shots were fired at an empty house in Hylton Road. Cleveland Police said they believed the shootings were linked. No-one was injured.
A 21-year-old man was arrested in connection with both shootings but later released without charge.
A black car was shot at by a cyclist at about 14:45 BST on Tuesday.
Police said a white car was also seen in Windlestone Road at the same time and all the occupants are believed to be known to each other.
The shots were fired at the house at about 22:40 BST on Wednesday.
Det Insp Jon Tapper said: "Incidents of this nature are thankfully very rare and detectives are doing everything possible to identify and trace those involved.
"These incidents are believed to be targeted."