A bus veered off a mountainous road in northwest Nepal Tuesday, killing 30 people and wounding 35 others, authorities said. The bus was crowded, with passengers even sitting atop it.

The accident occurred at Ramche village in Rasuwa district, about 93 miles north of capital Kathmandu. The bus rolled about 150 meters (500 feet) down a slope, Shiv Ram Gelal, a government administrator, said, according to the Associated Press (AP). Gelal added that the bus was packed because of a severe fuel shortage in the country that resulted in limited transportation services, AP reported. Police are investigating the accident.

Shiva Acharya, who escaped by jumping off the bus, said the bus veered off after a front wheel punctured, according to the Kathmandu Post, a local newspaper. According to AP, the fuel shortage forced people to travel on roofs of buses, with police rarely taking any action against it.

Nepali protesters have blocked a major border crossing with India since September, stopping import of fuel and other supplies.