Authorities want to introduce tolls of up to €22.50 on the main link between Kosovo and Albania. Protesters say the road should unite the two countries, both dominated by ethnic Albanians.
Several hundred protesters in Albania have brawled with police over the introduction of tolls on the country's main motorway link to Kosovo.
Police said 14 officers were injured after protesters pelted them with stones and burnt down toll booths near the Morina border crossing.
Local media outlets reported some protesters were also injured in the scuffles.
"All those who incited these barbarian acts against police officers and public and private property will be brought to justice," said Albanian Interior Minister Fatmir Xhafaj.
Meanwhile, the public prosecutor said it had launched a probe to establish "the criminal responsibility of those who violated the law."
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An important link
Authorities planned to impose tolls of €2.50 (around $3) for motorbikes, €5 euros for cars and €22.50 for trucks starting Sunday.
The 110-kilometer (70-mile) highway links the Albanian town of Milot, near the Adriatic coast, to the Morine border crossing.
The people of Kosovo — almost entirely ethnic Albanians — use the link to cross mountainous terrain and access the seaside they lack at home.
Earlier this week, more than 100 Kosovo truck drivers and hundreds of shopkeepers in the Albanian town of Kukes protested against the decision, displaying banners reading: "This road should unite Albanians, not divide them."
Work in progress
The road remains unfinished and an international consortium has been contracted to complete a segment link, maintain the road and collect tolls over a 30-year period.
Kosovo Prime Minister Ramush Haradinaj has said the tolls are "excessive."
Albanian Prime Minister Edi Rama, meanwhile, has said those who use the road should be the ones to pay for it.
aw/cmk (AP, Reuters, AFP)