Thirteen Sudanese police officers were killed and 30 wounded in clashes with an armed gang as they tried to rescue three hostages in the war-torn Darfur region, a police spokesman said on Friday.
"What happened yesterday involved an armed gang, not a rebel group. The police tried to release three hostages in eastern Jebel Marra. Clashes broke out with the gang and we lost 13 men and 30 others were wounded," Ahmed al-Tughani told AFP.
He was unable to provide further details, including on the identity of the hostages.
But Sudanese newspaper Al-Ahdath, citing police sources, said that one of the hostages was an Italian, another was a businessman from Nyala, the state capital of South Darfur, and the third was a police officer.
Last month, Italian humanitarian worker Francesco Azzara, who worked at a child-care centre in Nyala, was kidnapped as he was driving to the airport.
Azzara, 34, was in charge of logistics at the paediatric centre opened in Nyala by the charity Emergency in July 2010.
The Italian foreign ministry said on Friday that there were "no links between the case of Azzara" and the failed police operation, a claim supported by Emergency's president Cecilia Strada.
"According to our local sources, it appears that the police operation in Sudan does not concern our staff member Francesco Azzara," she was quoted as telling Italy's Ansa news agency.
Emergency, which has been operating in Sudan since 2004, has two child-care centres, in Nyala and the Mayo refugee camp near Khartoum, and a heart clinic at Soba, 20 kilometres (12 miles) from the Sudanese capital.
At least 300,000 people have been killed and 1.9 million people have fled their homes since the Darfur conflict erupted in 2003 between non-Arab rebels and the Arab-dominated Khartoum regime, the United Nations says.
The government says only 10,000 have been killed in the conflict and insists that the ongoing lack of security in Darfur is the result of tribal conflict, minority armed forces and banditry.
Speaking in New York on Thursday, Britain's UN ambassador Mark Lyall Grant told journalists that the security situation in Darfur was "still very bad."
There has been a wave of kidnappings for ransom since March 2009 when the International Criminal Court indicted President Omar al-Bashir for alleged war crimes and crimes against humanity in Darfur.
Around 30 foreigners have been kidnapped in Darfur since the indictment, with most of them released unharmed a few days later.
But three Bulgarian helicopter pilots, abducted while working under a UN contract, were freed in June after spending 145 days in captivity.
Following a relative lull, there have been sporadic clashes in Darfur since December between rebel groups and government forces that have displaced more than 70,000 people, according to UN estimates.