The bus (Na 4 Kha 9201) which was heading towards Kathmandu from Bahunepati in Sindhupalchowk with marriage attendees on board veered off some 100 metres due to its brake failure, according to the Area Police Office, Sankhu.
Of the total injured, three are in critical condition, said Umesh Joshi, Police Inspector at the Area Police Office, Sankhu.
Some 17 injured are receiving treatment at the Sushma Koirala Memorial Hospital while 13 are being treated at Life Care Hospital in Sankhu and critically injured ones were at Nepal Medical College at Jorpati.