U.N. Secretary-General Ban Ki-moon Sunday praised the Nigerian elections as largely peaceful, despite some technical glitches and attacks by terror groups before and during the country’s presidential and parliamentary elections. Ban also condemned the attacks reportedly carried out by Boko Haram and others attempting to disrupt the polling in a statement released his spokesperson.

“He is encouraged by the determination and resilience shown by the Nigerian people in pressing forward and exercising their civic duties in the face of unjustifiable violence,” said the statement. Ban encouraged Nigerians to maintain the peaceful atmosphere and patience as voting continued. Attahiru Jega, the chairman of the country’s election commission, said the first collated results would be available Sunday evening, Reuters reported.

Ban added a successful conclusion to the election would mark a historic step forward for the African democracy and for the rule of law in Nigeria. “He calls on all actors to channel any complaints that might arise through the established dispute resolution mechanisms,” the statement said.

Technical problems prevented some people from casting their ballots Saturday, the Associated Press reported. Millions of people waited in line for hours Saturday because of malfunctioning thumb scanners and a cyberattack on the country’s Independent National Electoral Commission website. About 350 polling stations were reopened Sunday because of the glitches.

The first day of voting came with violent attacks by supposed Boko Haram militants, leaving at least 41 people dead and sending people fleeing from polling places in northeastern Nigeria. In the southern oil-producing region, thousands of Nigerians protested the alleged killings of opposition campaign workers and voting irregularities, the AP reported. Jega, the elections commissioner, Sunday promised an investigation of the irregularities.