Two college students from Bihar were feared drowned in a canal in Dehradun district on Friday, police said, days after three youths had drowned in Nayar river in Uttarakhand's Pauri district.The incident occurred when the duo went to the Shakti canal near Dhalipur power project on a trip to the area around noon. Local people informed the police that the two youths had drowned with their bike found parked on the nearby road in the afternoon.Soon after getting the information, the police launched a search operation to recover the bodies. However, the bodies have not yet been found. Both victims were studying in a private college here.On Wednesday, three young friends, including an army jawan, had drowned in Nayar river in Pauri district when they tried to save each other. The incident occurred at Paithani area of the district where the trio along with some other friends had gone for a picnic on the river bank. All the three were in their early twenties and hailed from Pauri district, police said.As one of the youths started to drown in the river, the other two dived in to save him. But all the three were swept away in the fast currents.