Turkish police on Sunday (May 15) prevented dissidents in the nationalist opposition party from holding an extraordinary congress in Ankara.
Hundreds of party members seeking to reach the hotel where the meeting was scheduled were blocked by barricades and water cannons, according to media reports.
The congress aimed to unseat the MHP's longtime leader, Devlet Bahceli, whom they blame for the party's dwindling popularity.
"Bahceli resign, resign", the crowd chanted.
Bahceli's main challenger, former interior minister Meral Aksener, accused the ruling AK party of intervening to try to block the congress.
"Those who changed the Prime Minister in an hour are now displaying every unlawful and anti-democratic behaviour to prevent us from holding this congress," she said.
The AK party needs the MHP's support to change the Turkish constitution and give president Recep Tayyip Erdogan more powers. The dissidents, including Aksener, oppose the plan.