LIMA, Peru, (AFP) – Four of the Avengers swooped into a dangerous Lima neighborhood over the weekend, when Spider-Man, Captain America, Thor and the Black Widow broke down a door and arrested several wanted drug dealers.

The four “superheroes” were in fact members of a special Peruvian police squad pretending to be doing promotion for a Halloween concert, the police said in a statement on Tuesday.

The operation, dubbed “Marvel” after the comic book publisher of The Avengers, saw four officers dressed as superheroes walk nonchalantly down a street in the San Juan de Lurigancho neighborhood of Lima on Saturday.

Upon arriving at a specific house, Spider-Man and his friends whipped out special equipment and broke down a steel door, allowing 10 backup police members to enter and arrest three men and a woman.

The occupants, taken by surprise, at first thought it was a Halloween joke, according to police.

“In this building an entire family was dedicating themselves to the micro-commercialization of drugs. The drugs were going to be sold in a park nearby,” said police Colonel David Villanueva.

Police seized 3,250 small packages of basic cocaine paste — a crude extract of coca leaf — as well as 287 bags of cocaine and 127 of marijuana.

One kilo of cocaine paste sells for roughly $380 in Peru, while a kilo of cocaine hydrochloride, the purest form, sells for about $1,000.