Three people were spotted climbing out of a Brooklyn manhole early Friday – adding to a bizarre string of citywide sewer-diving incidents, cops said.

The sketchy trio emerged from the steamy pit at Bay Ridge Parkway and 17th Avenue in Bensonhurst around 4:30 a.m., catching the eye of a bystander who called 911, police said.

But the group of men – spotted wearing bright clothing –  were already in the wind by the time cops arrived and no arrests were made, authorities said.

The investigation was ongoing, police said.

It was not immediately clear whether the three underground criminals were also connected to any of the previous manhole incursions across the city.

In another incident just two days ago, three nightcrawlers embarked on a pre-dawn sewer escapade steps from the Upper East Side’s Loews Regency New York – where dignitaries including Israeli Prime Minister Benjamin Netanyahu were staying during the UN General Assembly.

Kevin Rodriguez, 26, and Samuel Reveron, 25 – both Queens residents and Venezuelan citizens – were arrested in connection to that stunt, cops and sources said.

Reveron laid out the greedy underground intruders’ motive when speaking with investigators, prosecutors said Friday.

“We go into the sewers to look for valuables that go into the sewer drains,” he allegedly told a police officer, specifying that they hoped to find “gold,” according to prosecutors.

A federal law-enforcement source briefed on the matter said that neither suspect appeared to have had malicious intent or posed any threat to the dignitaries staying at the hotel.

This year alone, elusive “mole people” were spotted popping out of manholes in Middle Village, Queens, Williamsburg and Gravesend in Brooklyn – and even near Manhattan’s bustling Penn Station and Madison Square Garden.