An Indian couple living in Italy allegedly killed their Iranian roommate and dumped her body in a Venice canal after she refused to participate in a threesome, according to media reports.

A suitcase with the body of 31-year-old Mahtab Avad Savoji stuffed inside was found by police last week, the Il Gazzetino newspaper reported, according to Italian news agency Adnkronos.

Savoji, a student at the University of Brera, lived in Milan with Gagandeep Kaur, 30, and Rajeshwar Singh, 28, according to the Daily Mail. They killed Savoji in Milan and then traveled across northern Italy to Venice, where they dumped the luggage containing her body near the Lido beach, according to police. An exam of Savoji’s body found that she died of asphyxiation. She didn’t have any water in her lungs, leading investigators to conclude that she was killed before being dumped in the canal. Kaur and Singh have been arrested on murder charges.

Police in Milan said the couple initially gave contradictory statements about Savoji’s death, which led authorities to hone in on Kaur and Singh as suspects in the murder, an English-language Indian news outlet, the Pune Mirror reported. “Then they said they found her in her room dead, panicked and put her in a suitcase,” Milan crime squad head Alessandro Giuliano told the website. “They first tried to dispose of the body in Lake Como, in Lecco, but were unable to do so because there were people around.”

Giuliano said the suspects took a train from Milan to Venice, and were seen on surveillance cameras with the suitcase.

Police believe Singh, a hotel porter, and Kaur, a maid, may have killed Savoji because she rejected Singh’s sexual advances. Savoji was supposed to move out of the Milan apartment on the day she was found dead. She had told friends she didn’t get along with her roommates.

Singh and Kaur face charges of murder and concealing a corpse, according to Il Gazzettino. They are reportedly cooperating with the investigation.