A mentally challenged girl was allegedly raped and killed by her brother and his three friends in Manoharpur area of Jaipur district, police said on Saturday.
The four suspects, aged 19-21, took the minor to a nearby forested area on May 17 and allegedly raped her. They then allegedly strangled her to death and dumped the body in a drain, police said.
The girl's father lodged a missing complaint on the next day after which police launched a search operation, Manoharpur SHO Ramswaroop said.
The girl's brother also accompanied the search team, he added.
After a detailed investigation, police zeroed in on the four suspects and detained them on Saturday, the station house officer said.