Chad has accused Sudan’s army of carrying out an air strike near their shared border that killed 12 people and wounded seven, adding another cross-border flashpoint to the Sudanese war.

According to Al Jazeera’s report on the event date, the strike hit a fuel market in Chad near the frontier with Sudan. A Chadian security source said the attack targeted a site where the Rapid Support Forces refuel, and officials blamed the Sudanese military for the deaths. The Chadian army said the strike took place more than 100 kilometres inside eastern Chad’s Ennedi region and that there were no Chadian military casualties.

The allegation came against the backdrop of a war in Sudan that has lasted more than three years and displaced millions of people. The conflict between Sudan’s army and the RSF has repeatedly drawn in neighbouring states through accusations of support, territorial violations and cross-border incidents.

Sudan rejected the accusation. Its foreign ministry said it was surprised by the claim before any professional and independent investigation into the incident. The ministry said the army was carrying out its constitutional duty to protect Sudan’s sovereignty and security while respecting the sovereignty of neighbouring countries and not targeting their territory.

The United States embassy in Khartoum also accused the Sudanese army of launching the recent strikes on Chad, according to Al Jazeera. That makes the episode diplomatically sensitive as well as militarily serious, because multiple actors outside the immediate conflict have now weighed in.

Chad has previously said Sudan was responsible for another strike that hit a military convoy inside Chadian territory last week. The repeated allegations suggest a pattern of escalating tension along a border that has already become strategically important in the wider war.

Chadian officials have also increased their security posture in response to drones and other threats. A security source told Al Jazeera that the alert level in the area had been raised to its highest point, and Reuters was cited as saying Chad had deployed about 100 armoured vehicles and signal-jamming trucks near eastern Tine, close to the border.

The geography is important. The border region is long, difficult to police and increasingly militarised. The people most exposed are local residents, traders and displaced civilians who move through or live near the frontier. Nearly one million displaced Sudanese people have fled into Chad, where they are already facing a water crisis.

That makes every new allegation of a strike more than a military dispute. It is also a humanitarian and political problem for a host country already absorbing a large refugee population. Any attack inside Chad risks deepening instability in a region where aid systems, border controls and civilian safety are already under strain.

For now, the facts on the ground are limited to the competing claims. Chadian officials say the strike killed 12 and wounded seven. Sudan denies violating Chadian territory. The U.S. embassy has added its own accusation. What remains missing is an independent investigation that can establish exactly what happened, who ordered it and whether the attack was deliberate, mistaken or something else entirely.