Multiple streets in Manhattan are closed this morning so crews can do street and building repairs in the area of last week's deadly crane collapse.

Much of the area surrounding where the crane fell, Worth Street, is at least partially blocked from traffic.

The street itself is almost completely closed between West Broadway and Hudson Street.

There are also closures on the northbound side of Church Street and the southbound side of West Broadway.

Mayor Bill de Blasio introduced new measures on Sunday to increase safety when large construction cranes are operating in the city.

There will now be new restrictions on crawler cranes during wind conditions, with cranes to be shut down if forecasts call for winds over 20 mph or gusts above 30 mph.

Neighboring residents and business owners will be notified about crane activities, and workers will step up enforcement of pedestrian safety alongside crane sites.

"Friday's incident obviously is a warning we take very seriously. We all know there's a construction boom going on in our city. Although we value the work that's being done, we value what it means for our economy, we valued that jobs are being created. Nothing is more important than the safety of our people. There's no building that is worth a person's life," said Mayor Bill de Blasio.

Officials say it could take weeks to determine the cause of Friday's collapse.

As the investigation into what caused the crane to collapse continues, mourners gathered Sunday to remember the man killed in the crash.

David Wichs, 38, was walking on Worth Street when the crane fell on him. 

A funeral for the Upper West side resident was held at a synagogue in Manhattan.

He was a mathematics whiz who worked at a computerized-trading firm.

Friends and family described him as cheerful, kind and humble. 

"Just always a smile, always happy to help just always part of the group, part of the gang," said Shaun Steigman, a friend of Wichs.

"I think families are broken when this happens and it'll heal ultimatley but only partly, it can't I mean everytime I think of him I think of my own three sons and I worry every single time," said Jacob Brandler, a high school mentor of Wichs.

Three others were injured by falling debris from the collapse.