An accused serial rapist who escaped from jail by climbing through a ceiling vent and rappelling down the building using tied-together bed sheets appears to have had help, the city's police chief said Thursday.

"Our investigation so far reveals some sort of conspiracy," Chief John Timoney told ABC's "Good Morning America." He said it involved at least one and probably two individuals, but didn't elaborate on whether he thought the help was inside the jail, outside or both.

Reynaldo E. Rapalo is accused of sexually assaulting seven girls and women in the Little Havana neighborhood in 2002 and 2003. He escaped Tuesday night from the jail where he was awaiting a February trial that could have sent him to prison for life. Another inmate, Idanio Bravo, also scaled down the building, but he fell, broke his legs and was caught.

Officers were scouring neighborhoods, airports, train stations and ports for Rapalo, a 34-year-old Honduran native, and guards have been assigned to victims who still live in the area.

Residents said they were concerned and angry that Rapalo was on the loose again.

Sandra Barahona, 24, said she remembers when police came to the area and posted sketches three years ago.

"Mothers were scared for their daughters," Barahona said. She said she and others wanted to know how Rapalo escaped from a maximum-security facility.

Said Ena Hernandez, 26, who works at a jewelry store in the neighborhood: "It makes me want to watch my back more."

Rapalo was the target of a major manhunt following attacks on girls and women from age 11 to 79. He was arrested in September 2003.

On Tuesday, officials said, Rapalo climbed through a vent in the 7-foot ceiling of his single-man cell on the sixth floor and made it to the roof. The vent was supposed to be locked but its door had been pried off. Bars blocking the vent's opening onto the roof were also cut, officials said.

Timoney couldn't explain Thursday why Rapalo was in a cell with a vent. "This is high-risk prisoner who's going to go away for the rest of his life. Clearly, he is a high escape risk," he told ABC.

Miami-Dade State Attorney Katherine Fernandez-Rundle warned that anyone who helps Rapalo will face the maximum penalty and asked for the public's help. By Wednesday afternoon, Little Havana stores had taped wanted posters to their front doors.

Authorities said Honduran officials assured them that if Rapalo tried to return there, they would try to help capture him.