A mother duck and her nine babies were crossing a New York City street when three ducklings fell through a storm grate and had to be retrieved by police.

The rescue happened Sunday in the bustling Brooklyn neighborhood of Park Slope.

Witness Lynn Harris told the news site Gothamist people had noticed the ducks and were following beside them, trying to provide a safe escort when the mother duck was spooked by a dog.

In this July 28, 2019 photo provided by Lynn Harris, NYPD SWAT team officers remove a storm grate to rescue three ducklings that fell into the drain while walking along Seventh Avenue in the Brooklyn borough of New York. The SWAT crew managed to rescue the ducklings and turn them over to a wildlife rehabilitator for evaluation before being released back into the wild. (Lynn Harris via AP)

In this July 28, 2019 photo provided by Lynn Harris, NYPD SWAT team officers remove a storm grate to rescue three ducklings that fell into the drain while walking along Seventh Avenue in the Brooklyn borough of New York. The SWAT crew managed to rescue the ducklings and turn them over to a wildlife rehabilitator for evaluation before being released back into the wild. (Lynn Harris via AP)

That's when three of her little ones dropped through the grate outside a hospital.

A crowd including animal rescuer Sean Casey gathered to help. Police officers opened the grate — but then dropped it into the hole.

A nurse peeked in and shouted, "They're alive!"

In this Sunday, July 28, 2019 photo provided by Lynn Harris, a mother duck leads her ducklings along a sidewalk on Seventh Avenue in the Brooklyn borough of New York. The ducks were crossed Sixth Street to avoid a dog when three of the ducklings fell into a storm drain. A pair of New York Police Department SWAT team members managed to rescue the ducklings and turn them over to a wildlife rehabilitator. (Lynn Harris via AP)

In this Sunday, July 28, 2019 photo provided by Lynn Harris, a mother duck leads her ducklings along a sidewalk on Seventh Avenue in the Brooklyn borough of New York. The ducks were crossed Sixth Street to avoid a dog when three of the ducklings fell into a storm drain. A pair of New York Police Department SWAT team members managed to rescue the ducklings and turn them over to a wildlife rehabilitator. (Lynn Harris via AP)

The ducks were then taken to a shelter.