Casualties have been reported after simultaneous explosions hit two local headquarters of the Kurdish problem-focused Peoples' Democratic Party (HDP) in the southern Turkish provinces of Adana and Mersin on Monday, May 18, according to Hurriyet Daily News.

A loud explosion rocked the second floor of the building where HDP's provincial HQ is based in Adana at the same time as an explosion at the party's Mersin branch. Eyewitnesses said there were casualties.

According to the HDP headquarters in Ankara, the explosion in Adana occurred in the cargo room of its local branch. In its Mersin branch, a flower bouquet that was sent Sunday exploded when it was unpacked.

Citing Mersin police chief Rahmi Baştuğ, Turkey's semi-official Anadolu Agency said that the explosion in Mersin occurred in the kitchen of the HDP's local branch.

HDP Co-Chair Selahattin Demirtaş was set to hold a campaign rally in Mersin on Moday, ahead of the June 7 general election.

The incident marks the latest in a number of attacks against HDP offices across Turkey.

The HDP says it has been exposed to 56 attacks over the course of just one month across Turkey, according to the Dicle News Agency. These attacks include attempts to target 16 election bureaus, and two of the attacks were armed.