Police shut down part of Old Sambro Road Monday morning after a suspicious package was discovered in a house. (Blair Rhodes/CBC)

Halifax Regional Police arrested four men after an investigation of a drive-by shooting led to a search that shut down part of Old Sambro Road in Williamswood on Monday morning.

Police were called to Robie and McCully streets around 2:15 a.m. Saturday. There, a taxi driver approached them, and said he had been involved in a shooting.

The taxi was driving a passenger northbound when a silver car pulled up and someone started shooting at the cab. No one was injured.

The passenger fled the cab as soon as the driver pulled over.

Then Monday, Const. Pierre Bourdages said they searched three different locations — one in Williamswood and two in Halifax.

"I can't go into detail as to what led them to these addresses," he said.

Shortly after, the police arrested four men in their twenties. All four are known to police, said Bourdages.

Suspicious package

While searching the home in Williamswood, one officer came upon a suspicious package. Bourdages said the officers determined it was unsafe and they evacuated the house.

The explosive disposal unit was called in and a section of the 2400 block of Old Sambro Road was shut down. The package was removed from the house with the help of a bomb disposal robot.

"They will be conducting more testing on it to determine what the composition is," said Bourdages.

Old Sambro Road was reopened to traffic just before 1:30 p.m.