* Two days of violence after ex-guerrilla made defence minister
* Ethnic tensions still simmer since 2001 insurgency
* Slow progress towards membership of NATO and EU
Riot police in Macedonia clashed on Saturday with ethnic Albanian protesters who torched a bus and attacked shops in a second day of violence triggered by the appointment of a former guerrilla fighter as defence minister.
Ethnic tensions continue to simmer in the impoverished former Yugoslav republic more than a decade since it was brought to the brink of civil war during an ethnic Albanian guerrilla insurgency.
Saturday's violence, in which at least 20 people were injured and a dozen arrested, appeared to be a response to angry demonstrations by Macedonians late on Friday against the appointment last month of former guerrilla commander Talat Xhaferi as defence minister.
Several hundred ethnic Albanians in the capital, Skopje, torched a bus and several cars, and attacked shops. Police in riot gear fired tear gas and stun grenades to disperse them, a Reuters photographer said.
"The situation is under control. A dozen people have been arrested, while the others fled," said a police spokesman. "Police are on the ground and working on finding the others who took part. The material damage is great."
Xhaferi was part of a guerrilla army that fought for greater rights and representation for Macedonia's 25 percent ethnic Albanian minority.
The West brokered a deal whereby the guerrillas disarmed and entered politics, and one faction is now in coalition government with rightist Prime Minister Nikola Gruevski.
But relations remain tense, exacerbated by the slow pace of progress in Macedonia towards European Union membership and the freedom of movement and economic opportunity the country's 2 million people hope this will bring.
Macedonia's bid to join the EU and NATO is being held hostage to a long-running dispute with neighbouring Greece over the country's name, which it shares with a northern Greek province. Greece wants it changed.
Mindful of the threat of instability, the EU has signalled it might agree to open accession talks with Macedonia this year even without a solution to the name dispute.