No officers were injured, the Belfast Telegraph reported. Chief Superintendent George Clarke appealed for public help in apprehending the shooters and said the attack would be treated as attempted murder.
The attack occurred in the Ardoyne neighborhood in north Belfast, a republican stronghold during the Troubles that quickly became a "no-go" area for what was then known as the Royal Ulster Constabulary.
Earlier Thursday, two men who had been detained for questioning about an abortive car bombing in Belfast were released without charge. On Nov. 24, a car was hijacked in the Ardoyne and the driver forced to take the bomb to the center of the city.
The driver managed to ditch the car and warn the authorities about the bomb. The bomb partially detonated without injuring anyone.
Nigel Dodds, a unionist who represents north Belfast in the British Parliament, condemned Thursday's shooting and said there appears to be a pattern of new violence.
"There does appear to be a growing dissident threat within Ardoyne and we have seen the intent and capability of these terrorists in Belfast all too clearly in recent weeks," Dodds said.
Gerry Kelly, a member of the provincial legislative assembly and the republican Sinn Fein party, said the dissidents should come forward and explain themselves.
"Those behind this attack are serving their own narrow agenda and are in no way representative of this community," he said.
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