A court in the Pakistani capital has ordered protection for two teenage sisters from the minority Hindu community as investigators widen a probe to determine whether the girls were abducted and forced to convert and marry two Muslims.

The Islamabad High Court issued the order on Tuesday, saying the girls had petitioned the tribunal seeking protection for themselves and their husbands the previous day.

The girls and the husbands, all from the southern town of Ghotki in Sindh province, were sent to separate government shelters.

According to police, the girls' parents say their daughters are 13 and 15 years old.

Earlier, police arrested several suspects in the case, including a cleric who performed the wedding last Friday.

Underage marriage is illegal in Pakistan but the law is often ignored.