Manhattan prosecutors are expected to announce manslaughter charges on Monday against the rigger who was overseeing the raising of a tower crane on the East Side last year when it collapsed, killing seven, according to people briefed on the case.

The rigger, William Rapetti, has also been charged with criminally negligent homicide, reckless endangerment and second-degree assault in the spectacular disaster, in which the 22-story crane plunged across East 51st Street, piercing one building and tearing terraces off another, the people said. The accident, on March 15, played out across a two-block swath of the Turtle Bay neighborhood, leaving two dozen people injured and the streets strewn with rubble.

The charges  including seven counts each of second-degree manslaughter and criminally negligent homicide  are contained in an indictment that is expected to be unsealed on Monday, the people said. Mr. Rapetti’s company, Rapetti Rigging Services, will also be charged, the people said. All spoke on the condition of anonymity because the charges remained sealed.

Mr. Rapetti, 48, of Massapequa Park, N.Y., was set to surrender on Monday morning, said his lawyer, Arthur L. Aidala, who noted that five of the seven people who died were friends of his client’s, men working with him on the crane that day.