Mogadishu - A regional administration in Somalia said rival forces deliberately misled the US into launching an air strike that killed 13 of its troops and wounded seven others.

The US confirmed conducting the strike on Wednesday morning near the town of Galkayo, but said it targeted the Shabaab, an al-Qaeda group.

"During a Somali-led counter-terrorism operation to disrupt an al-Shabaab Improvised Explosive Device (IED) making network, a group of armed al-Shabaab fighters attacked, threatening the safety and security of the Somali force and their US advisors," the US Africa Command said in a statement.

"Somali forces returned fire in self-defense. The US conducted a self-defense strike to neutralize the threat, killing nine enemy fighters."

However, authorities from Galmudug state say it was their soldiers who were killed and that the US was duped by troops from neighbouring Puntland state into carrying out the strike.

Apology and compensation 

"The administration of Galmudug State of Somalia is very disappointed that the US Pentagon has used an excessive force against Galmudug forces with misinformation from another regional state in Somalia," Mohamed Adan Osman, Galmudug's information minister, said late Thursday.

"We suspect that Puntland State of Somalia provided wrong information deliberately with its own interest to secure the attack."

It is unclear whether the strike, which according to Galmudug authorities killed 13, was a case of mistaken identity or a result of hostility between the restive neighbouring states.

Another Galmudug spokesman, Mohamed Hassan Sahal, told AFP a fragment of a US missile had been found at the scene of the attack, which came after Galmudug soldiers had clashed with those from Puntland.

Puntland denied the charge insisting that Shabaab militants were targeted.

"The operation was targeting Shabaab fighters who were in the process of organising attacks against Puntland," said Abdinasir Baddal, a Puntland state official told reporters.

Somalia's cental government has asked the US "to provide a clear explanation for the attack" while Gulmudug state has called for an investigation as well as "an apology and compensation".