Lawrence, Mass. ? Six boys plunged Saturday through the soft, thin ice of the Merrimack River, and four who were trapped below for several minutes later died.

Two of the boys were merely “cold and wet” after rescuers quickly retrieved them, Deputy Chief Joseph Marquis said.

The other four had been trapped under the ice for at least 10 minutes, and were unconscious Saturday afternoon when they were pulled from the river, said Lawrence Police Chief John J. Romero.

William Rodriguez, 11, Victor Baez, 9, Mackendy Constant, 8, and Christopher Casado, 7, were declared dead at hospitals.

The boys had walked out on the one- to two-inch thick ice about 25 feet from shore. They were either returning from, or on their way to an event at the nearby Lawrence Boys and Girls Club, Romero said.

A seventh child, Christopher Casado’s 9-year-old brother, Ivan, stayed on the bank and ran to a nearby house to call for help when the children fell through the ice.

A man who lives in the house, Jacques Fournier, called emergency personnel and then tried to rescue them himself with a rope.

A child is carried by a rescue worker after being pulled from the Merrimack River in Lawrence, Mass. Emergency workers on Saturday pulled six children out of the river. The children had plunged through thin ice Saturday as they played on the Merrimack. Four of the children died.

Arriving police formed a human chain and were able to pull out the two children closest to shore even after falling through the ice themselves, Romero said. It was then that they learned four more children still were trapped.

“Everybody pitched in and worked together,” said Romero, applauding rescue workers who went into the river after the children.

“My heart goes out to the children’s families,” he added.

Temperatures were in the mid-40s on Saturday.