DIYARBAKIR, Turkey — Kurdish celebrations of springtime on Tuesday mixed peacefully with protests against expanding the powers of Turkey's president.

Thousands celebrated the Newroz festival in Istanbul and in Diyarbakir, a mainly Kurdish city in a region where Kurdish militants regularly clash with government forces. Many flags proclaimed "No" in the Turkish and Kurdish languages, referring to President Recep Tayyip Erdogan's bid to gain more power for his office in an April 16 referendum.

In Turkey, the spring festival traditionally serves as an occasion to demand more rights for the Kurdish minority.

Some celebrants also carried banners supporting the People's Democratic Party, or HDP, a pro-Kurdish political party whose top leaders have been arrested under Turkey's anti-terror laws and are accused by the government of links to Kurdish rebels.

The HDP, which denies such links, is the nation's third-largest party and opposes the referendum. However, the ruling Justice and Development Party enjoys the support of some Kurds who could vote in favor of the referendum proposals.

Erdogan has said an executive presidency will stabilize Turkey and enable it to deal with economic, security and other challenges, while opponents describe it as part of a dangerous drift toward authoritarian rule.

A few Kurds in the festival crowds carried flags with the image of Abdullah Ocalan, the jailed leader of the rebel Kurdistan Workers' Party, or PKK. The group has been fighting a separatist insurgency against the Turkish state since 1984.

Turkish authorities nonetheless permitted the celebrations to proceed.

In Diyarbakir, police mostly kept their distance from the event, allowing Kurdish guards to search people and keep order. People performed traditional dances and watched a big bonfire.

Police fatally shot one man who tried to flee from the festival area after being discovered with a knife, the Dogan news agency reported.

Newroz, the Farsi-language word for "new year," is an ancient Persian festival that is celebrated in countries including Iraq, Turkey, Azerbaijan, Afghanistan and Iran.