NEW DELHI, India (AP) — An American woman was gang-raped yesterday in the northern Indian resort town of Manali, police said.

The 30-year-old woman was picked up early yesterday morning by men in a truck as she was hitchhiking back to her guest house after visiting a friend, police officer Sher Singh said.

The three men in the truck then drove to a secluded spot and raped her, he said. She went to police and they filed a rape case.

No arrests had been made as of Tuesday afternoon, Singh said.

Authorities issued an alert for the three men and set up roadblocks to check any trucks leaving the town, he said.

The reported rape came after a Swiss tourist was gang-raped in March while on a cycling trip through rural India. Six men were arrested in that attack. In a separate incident the same month, a British woman traveling in northern India jumped out of the third-floor window of her hotel room fearing a sexual attack after the hotel’s owner tried to force his way into the room.

The assaults come amid heightened concern about sexual assaults in India that followed the fatal gang-rape of a young woman on a moving bus in New Delhi in December.

That rape sparked public protests demanding better protection for women. In response, the government passed a law increasing prison terms for rape and providing for the death penalty in cases of rape that result in death or leave the victim in a coma. It also made voyeurism, stalking, acid attacks and the trafficking of women punishable under criminal law.