Togolese authorities blocked Internet access on Thursday as opponents of President Faure Gnassingbe marched for a second day against his family’s 50-year rule.

Hundreds of protesters began marching from the opposition stronghold of Be towards a meeting in central Lome with police officers walking calmly besides them, a witness said.

The scale of this week’s protests, which the opposition says were attended by hundreds of thousands of people, represent the biggest challenge to Gnassingbe’s rule since the aftermath of his ascension to power in 2005.

In the past, security forces have violently suppressed protests, killing at least two people during an opposition march in August and hundreds after a contested election in 2005.

U.S.-based company Dyn, which monitors the Internet, said traffic dropped off at 0900 GMT in what critics say was a move by the government to suppress protests as other African incumbents have done. Residents said that text messages had also been blocked.

The communications minister could not immediately be reached for comment on the cuts. Analysts say he may find himself isolated amid growing criticism of autocratic rule in West Africa. Read full report here.