Story highlights Demonstrators storm Mali's presidential palace on Monday

Interim President Dioncounda Traore is beaten and taken to a hospital

A spokesman for rebel military officer says 3 people were killed by Traore's bodyguards

Traore was picked to lead an interim government after a March coup

Dioncounda Traore, Mali's interim president, was beaten and rushed to a hospital after hundreds of protesters demanding his resignation stormed the presidential palace Monday.

Traore was assaulted and hit over the head when protesters found him inside the palace. The president was later taken to the hospital where he was treated for a wound to his head, hospital staff said.

"There were three dead and some injured by gunshot when [Traore's] security shot at people," said Bakary Mariko, a spokesman for the National Committee for the Restoration of Democracy, a group of military officers who mounted a coup in March.

Protests were expected after the Economic Community of West African States, which has tried to broker a return to civilian rule after the coup, agreed to let Traore remain in charge for a year to oversee the transition. And ECOWAS has warned that followers of Capt. Amadou Sanogo, who led the revolt that deposed President Amadou Toumani Toure, were threatening to derail the agreement.

Traore's term as interim president had been set to expire on Tuesday. Groups denouncing him gathered Monday morning in the Place de l'Independence, in the center of Mali's capital, Bamako.

JUST WATCHED Events leading to military coup in Mali Replay More Videos ... MUST WATCH Events leading to military coup in Mali 01:10

JUST WATCHED Erin Burnett's message for Mali Replay More Videos ... MUST WATCH Erin Burnett's message for Mali 02:11

Traore "is not staying as president of Mali," said Youssouf Kone, the leader of several groups demanding the interim president's resignation.

"We will stay until Traore agrees to step down," he added. "We're going to make this the Tahrir Square," referencing the 2011 protests in Egypt.

Just before 11 a.m. (7 a.m. ET), a group of protesters parted and moved up the hill in direction of the presidential palace.

"We don't want Dioncounda" and "Down with ECOWAS," chanted a couple in the crowd, which remained peaceful at that point.

When it reached the palace gates, the spontaneous march had gathered a couple of hundred supporters, some of them shouting slogans in support of the coup leader, Sanogo. According to witnesses, soldiers stood by as the crowd entered the building while others climbed over armored vehicles parked nearby. Some protesters were seen parking motorbikes and bicycles inside the palace.

In other parts of town, protesters burned tires and put up posters saying the country will never heal with Traore in power. The group closed of one of the city's bridges, causing the traffic to stand still all over Bamako.

The protests reflect longstanding frustrations with Mali's political class. Several of the protesters expressed discontent with Traore, a former labor activist who was the country's parliament speaker before his appointment as interim president in April.

"Traore is part the same self-serving political elite that has misruled the country for years," Fadima Sy, one of the protesters in Place de l'Independence, said.

Interim Prime Minister Cheick Modibo Diarra went on state television Monday evening to denounce the attack and appealed to local politicians and organizations to stop encouraging the youth to march.

Mali had been hailed as a shining example of African democracy before the coup, having experienced more than 20 years of democratic government. Sanogo and his fellow officers ousted Toure on March 22, complaining that he had failed to properly equip soldiers battling a growing insurgency by Tuareg rebels in the country's north.

While ECOWAS and other countries pressured Sanogo to relinquish power, Tuareg fighters and Islamic rebels swiftly advanced and now claim control of much of northern Mali.