Political and community representatives have appealed for calm at a north Belfast interface following fresh trouble.
Petrol bombs were thrown towards homes in a Catholic area of Alliance Avenue, Ardoyne and two Protestants were taken to hospital following claims of attacks by Catholic gangs in the area.
Two petrol bombs were reported to have been thrown from loyalist Glenbryn Park towards Catholic homes on the other side of the peaceline.
A former North Belfast Assembly member, Mr Billy Hutchinson of the Progressive Unionist Party, has held talks with the PSNI about the tensions in the area.
A community representative, Mr Mark Coulter of the Greater Glenbryn Community Initiative, has called for firm police action to calm tensions after what he claimed were a series of attacks on Protestants.
Citing a series of alleged incidents, Mr Coulter said in a statement: "This is not the two communities at each other's throats, but simply a case of a few idiots on the green side of the peaceline trying to get things whipped up again."
He added: "People don't want a repeat of the chaos we have seen at interfaces in the past. "
The incidents, alleged to have taken place late on Monday, followed stone attacks on two school buses.
Windows were broken on buses serving Holy Cross girls' primary school in Ardoyne and Our Lady of Mercy school in nearby Ballysillan. No-one was injured in either incident.