Police in Gabon arrested dozens of people on Sunday over a knife attack in the capital apparently committed in retribution for "US attacks against Muslims", officials said.
The men detained were mostly traders and sellers in the popular market in Libreville where the attack occurred on Saturday -- and all are from west Africa, according to an AFP correspondent.
They were taken to police headquarters were they are due to be questioned, an official said.
"Operations are ongoing," government spokesman Alain-Claude Bilie By Nze told AFP. "We are not commenting at this stage."
Two Danish nationals working for the National Geographic channel were wounded in the attack, he said.
Police said the assailant is a 53-year-old Nigerian man who, according to witnesses, shouted "Allahu Akbar" (God is Greatest) during the attack.
The man, who has lived in Gabon for 19 years, said in his first statements that he "acted in retaliation for US attacks against Muslims and America's recognition of Jerusalem as Israel's capital," Defence Minister Etienne Massard said Saturday.
Residents said the man was from the Muslim Hausa/Fulani community of northern Nigeria and sold smoked meat from a cart in the city and in the market.
"We are still gathering information," Bilie By Nze said.
The market in Libreville, popular with tourists, was shut down after the incident and remained closed on Sunday, with security forces manning the gates.
Authorities have said the attack appeared to be politically motivated, but have not publicly classified it as terrorism.
Gabon, a small French-speaking former colony with 1.8 million inhabitants, has so far been spared the Islamist-inspired attacks that have taken place in some neighbouring countries.