Mexican federal police surrounded a university packed with leftist protesters in conflict-ridden Oaxaca City on Thursday, clearing barricades and firing tear gas as the activists showered them with gasoline bombs.

About 200 police wearing body armor and carrying riot shields advanced to the gates of the public university, but didn't actually enter the campus. Under Mexican law, the university rector must give the police permission to enter.

There were no immediate reports of injuries but two protesters were seen being detained by the police.

The protesters are demanding the resignation of Oaxaca Gov. Ulises Ruiz, whom they accuse of rigging the 2004 election to win office and organizing bands of thugs to attack dissidents.

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At least eight people have died in the conflict since leftist protesters took over the city five months ago. Among them was activist-journalist Bradley Roland Will, 36, of New York, who died in a gunbattle Friday.

The state prosecutor's office said Wednesday that two people were in custody and authorities were expected sometime this week to present the suspects to a judge who would decide whether to charge them in connection with Will's death.

The suspects are municipal officials of Santa Lucia del Camino, on the outskirts of Oaxaca, where Will was killed. They were detained after residents identified them as the people who shot Will, the state prosecutor's office said in a news release.

People are often detained in Mexico for questioning. Many are often released after police fail to find evidence to charge them.

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