"We have arrested more than 200 looters since last night," national police chief Jean-Thierry Oye
"Six police officers have been injured," Oye
He did not confirm however there had been any deaths.
"I can't tell you that," he said.
AFP journalists saw two trucks packed with dozens of detainees, who raised their fists in the air and chanted the Central African country's national anthem as they were driven off for questioning.
Violence erupted on Thursday after President Ali Bongo was declared the winner of the contested polls, with thousands of angry protesters taking to the streets of Libreville accusing the government of stealing the election from rival Jean Ping.
The opposition leader said security forces killed two people and injured 19 more at his headquarters.
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