These cops are on the sweets beat.

Police delivered a cake and sung “Happy Birthday” to cheer up Alexander, a 9-year-old Bronx boy who was sad he had to spend his birthday inside under the coronavirus lockdown.

Four officers from the 49th Precinct posted the video Tuesday of the heartwarming scene as they sang to the boy from a safe social distance.

“When we heard this young 9yr old child was a bit discouraged he couldn’t celebrate his birthday outside, we wanted to make sure his day was a memorable one by stopping by with birthday cake, the precinct said on Twitter.

The Police Department, along with the MTA, has been among the hardest-hit New York agencies during the coronavirus crisis. As of Monday, 4,435 members of the NYPD have tested positive for the virus since the outbreak began with at least 31 members of the force dying from the disease.

The video “brings me so much joy,” tweeted Bronx State Sen. Alessandra Biaggi. “Thank you @NYPD49Pct for going above and beyond to support our community through this difficult time.”