Two teenage sisters, who were allegedly raped by two co-workers of their father at a brick kiln in Rajasthan's Alwar district for 18 months, are pregnant, said police officials on Monday.

The girls' father lodged a complaint on Friday in this regard. In the complaint, he alleged that his daughters, aged 15 and 13, were raped by two accused Sappi and Subhan.

The family came to know when the elder girl complained of abdominal pain and other health problems. Her parents took her to a doctor, who confirmed that she was seven-and-a-half months pregnant, the police said.

"As her parents asked her, the girl told them that Sappi and Subhan had raped her and said that they had raped her younger sister as well," the police added.

The victim alleged that the accused had threatened them of dire consequences, if they disclose the incident.

Superintendent of Police (Alwar) Anand Sharma said an FIR was registered  on Friday and the girls' medical examination has been conducted. The medical test confirmed that both girls are pregnant.

The younger victim is two-and-a-half months pregnant, the police said.(IANS/NJ)