Chad's president has ordered the military to retaliate against future attacks from Sudan following a drone attack that killed at least 17 people and injured several other people attending a funeral.

Wearing military uniform, President Idris Mahamat Déby convened an emergency security meeting on Wednesday evening, where he ordered the military to be on high alert. He also ordered a total closure of the border with Sudan.

He described the attack targeting the border town of Tiné as outrageous and a blatant aggression against Chad's territorial integrity.

He said that it had happened despite warnings to the two sides battling each other in Sudan and a previous closure of the border.

Last month, Chad closed its border with Sudan until further notice to stop repeated incursions by Sudanese armed groups. It however allowed exceptional exemptions on humanitarian grounds, with prior authorisation from relevant authorities.

Residents of Tiné said the victims of Wednesday's attack were mourners, with one quoted by the Reuters news agency as saying they had gathered at a house for a funeral ceremony that involved reading the Koran.

The attack was condemned by the National Assembly and MPs from the ruling party. A statement by the government spokesman expressed condolences to the bereaved families while reaffirming Chad's commitment to defend its territory.

The paramilitary Rapid Support Forces (RSF), suspected of carrying out the attack, deny involvement, placing the blame on Sudan's army. Sudan has historically accused Chad of assisting the RSF, a charge N'Djamena vehemently denies.

Sudan has been engulfed in civil war since April 2023 due to a brutal power struggle between its army and the RSF, leading to a humanitarian crisis with over 13 million displaced.

Chad shares a long and porous border with Sudan, and this escalation of tensions could signify a troubling development for regional stability.