Clan wars are complicating the security situation in insurgency-ridden parts of the Philippines, distracting the government from peace-building efforts, the Red Cross warned on Thursday.
The blood feuds, known in Muslim areas as "rido", have caused mass displacement of civilians, said Jean Daniel Tauxe, country head of the International Committee of the Red Cross.
"Many communities still live in fear as internal clan disputes often referred to as rido continue to cause displacement and loss of lives," Tauxe told reporters.
"Thousands and thousands are displaced for short periods because of rido."
The government has been distracted from peace-building efforts as military and other resources are diverted to help end the clan wars, he said.
Tauxe said ICRC volunteers handed out food and other aid to about 600 families in the southern town of Kabacan on restive Mindanao island after commanders from two Muslim rebel factions fought over land at the start of 2011.
Both sides fired mortars and high powered rifles at each other in weeks of fighting that left at least 19 dead before local elders intervened and brokered a truce early this month.
The rido phenomenon came to the fore after a powerful Muslim clan allegedly massacred 57 people in the Southern town of Maguindanao in November 2009 in a failed bid to stop a rival from another family from seeking a government post.
The rival clans had ruled the province for decades and were known to control thousands of armed followers.
Clan fighting also leads to other violence, including destruction of property and kidnapping for ransom among warring clans, Tauxe said.
He said a culture of settling differences through violence, and the government's failure to clamp down on private armies controlled by large families were chiefly to blame.
"As long as you have private armies or people wearing weapons for private interests, this would always create problems," he said.
The Asia foundation, a think tank which had closely studied rido, says that from 2000 to 2004 alone, there had been around 637 cases of rido, or an average of 127 incidents a year.