35 protesters were arrested in Ferguson, Missouri Wednesday afternoon as they attempted to block traffic on an interstate in a planned demonstration that called for a special prosecutor to investigate Michael Brown's death.

The death of Michael Brown, an 18-year-old unarmed teenager who was shot by a white police officer on Aug. 9, has sparked national outrage and a string of protests in Ferguson. The police department maintains that Brown reached for Officer Darren Wilson's weapon before he was fatally shot, however several witnesses say the African-American teen was shot execution style while he was trying to surrender.

On Wednesday, demonstrators tried to shut down Interstate-70 as they demanded that a new prosecutor be appointed in the case, Mashable reports. According to protesters, St. Louis County prosecutor Robert McCulloch has strong family ties to the police department and a history of protecting police officers. Critics also note that McCulloch's father was an officer who was killed in a shootout with a black suspect back in 1964.

In addition, over 115,000 people nationwide have signed an online petition demanding that he be removed from the case.

Although demonstrators tried to block I-70, they were barred by the police from entering the highway. Most of the 35 people arrest were made for unlawful assembly, while four others were brought into custody for assaulting officers, reports the New York Times.

"I want to see justice served here," said demonstrator Charles Brooks, when asked why he came out to protest. He was among a group of people who sat down in the road, shouting: "McCulloch got to go! McCulloch got to go!" before he was arrested by officers and sent to the Missouri Department of Corrections, reports the NYT.

"The decision to appoint a special prosecutor in this case is a moral decision, not a political one," local activist Zaki Baruti declared in announcing the protest, according to the Washington Post.