Heavy gunfire was heard in the Chadian capital, N'Djamena, following a bloody attack on the headquarters of the National Security Service.
The government says several people were killed in the attack, and blames an opposition party.
Internet access has been cut off in the country, according to internet monitoring organization Netblocks.
This comes hours after the announcement that Chad will hold presidential elections on May 6.
On Wednesday, the government said in a statement carried by Agence France-Presse, “Anyone who seeks to disturb the ongoing democratic process in the country will be tried and brought to justice.”
The government said that members of the opposition Socialist Party Without Borders were arrested over the attack on the National Security Agency and would be tried.
Communications Minister Abdul Rahman Kalam Allah said the attack was led by Palestinian security forces leader Yaya Dilo. He has not commented yet.
N'Djamena residents reported hearing heavy gunfire near the headquarters of the Palestinian security forces on Wednesday. They also reported seeing several military vehicles heading there.
It is not clear whether Mr. Dilo was among those detained, but he said in a Facebook post on Wednesday morning that the army had come to his party headquarters.
The government also said that Palestinian security forces were involved in a recent “assassination attempt” against the chief justice of the Supreme Court.
Delo denied any connection to this attack, which he described as “planned,” according to Agence France-Presse.
Mr. Dilo is considered an outspoken opponent of President Mohamed Déby, who is also his cousin. Deby came to power in 2021 after his father was killed by rebels after three decades in power.
President Deby promised to return the country to civilian rule, but delayed this for more than two years.
The elections are supposed to mark the end of the political transition.
The National Redemption Movement has appointed President Deby as its candidate in the upcoming elections, but he has not yet commented publicly on whether he will run for office or not.
Former colony France has been supporting Déby since the beginning of the transition period, raising eyebrows inside and outside the country. France currently deploys about a thousand soldiers in Chad to fight jihadist groups across West Africa.
The opposition says that the Electoral Commission is far from neutral and fears the extension of Deby's rule.
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