Police fired teargas in clashes with demonstrators in the capital Niamey while in Dosso, 100 kilometres (60 miles) south of the city, the offices of a pro-government party were damaged by fire.
Alhada says, one of the two fatalities died of an epileptic fit during a protest. The other, who was shot dead, was the bodyguard of politician Seini Oumarou, an unsuccessful candidate in the first round of voting on December 27 who had urged supporters to vote for Bazoum in the runoff.
There was also destruction of infrastructure, of public and private property. Unknown assailants also attacked the home of a reporter in Niamey for Radio France Internationale (RFI), which is widely followed in Niger.
Journalist Moussa Kaka, who was unharmed in the attack, said assailants ransacked his home early breaking everything, and set fire to part of it.
Kaka, a veteran correspondent for RFI, spent 10 months in prison from 2007 to 2008 on charges of endangering state security over alleged ties with Tuareg rebels in northern Niger.