MP Oleksandr Ponomaryov of the People's Will group had a heart attack on 29 June, the Zaporizhzhya news website IPnews has quoted its sources as saying.
According to its information, the 56-year-old MP was rushed from Berdyansk to a hospital in Zaporizhzhya.
On 18 May, Prosecutor-General Yuriy Lutsenko asked parliament to lift Ponomaryov's immunity from prosecution for obstructing journalists' work.