NEW YORK — A police security tower rose into the sky Monday, keeping watch over a globally prominent Islamic cultural center that was firebombed amid a handful of attacks being investigated as possibly linked bias crimes.

Police, who had made no arrests, released a sketch of a suspect and a videotape from a surveillance camera at a private house that was one of the targets.

The video shows a car pulling up Sunday night. Someone suddenly appears, lifts his right arm high and hurls a lit object that strikes the house and explodes into flames.

Earlier Sunday evening, the entrance to the Imam Al-Khoei Foundation also was struck by two Molotov cocktails, the types of bombs usually made of glass bottles filled with flammable liquid and corked with rags.

“But we are not afraid,” said the center’s assistant imam, Maan Al-Sahlani.

With New York Police Department cruisers parked outside and yellow police tape fluttering, Al-Sahlani met Monday with a dozen other clerics from the city’s Muslim community. A news conference was planned for today, the imam said.

Near a blackened, charred spot on the concrete overhang of the center’s main entrance, the front gates remained wide open to the street Monday, and anyone could walk in to worship.

“This is America, and we must continue to love one another,” Al-Sahlani said with a smile.

On Sunday, about 80 faithful had gathered inside for dinner when a firebomb struck at 8:44 p.m.

A second one followed, striking a banner for the center’s school over the door. There was no visible damage there.

The other two targets in the suspected arson attacks Sunday night were a corner store and another house. No one was injured in any of the attacks.

Structural damage to the Queens Islamic center building was minimal, but the community was emotionally shaken, the Muslim cleric said.

His decades-old foundation is among the foremost Muslim institutions in New York, with branches around the world. Named for one of the most influential Shiite scholars, it promotes work in development, human rights and minority rights as a general consultant to the Economic and Social Council of the United Nations.