New York, New York - New York authorities on Friday pledged a full investigation into how a residential building collapsed this week, killing eight people and injuring over a dozen more.

The three-story property in Brooklyn tumbled into a neighboring excavation site on Wednesday afternoon, prompting a huge emergency response as firefighters pulled people from the rubble.

"The families in this community deserve answers about what led to this collapse," New York Attorney General Leticia James told reporters.

"And I have faith that the investigators will follow the facts, and that anyone found responsible will be held to account," she said, noting that Brooklyn's district prosecutor had launched a criminal probe.

New York's fire department declared Thursday afternoon that there were no further victims at the site after emergency workers spent hours searching with drones and dogs.

Two children were among the eight dead, with victims' ages ranging from nine to 31.

Officials have only begun investigating the collapse, but attention has focused on the neighboring construction site, where foundations were being prepared for a planned nine-story property.

City Council Speaker Julie Menin told reporters she wanted to strengthen New York's building codes and regulations after the collapse.

"This is an unspeakable, horrendous tragedy, and we must meet this moment," she said.