HANGZHOU, May 25 -- A man who fatally stabbed one doctor and wounded two others in east China was executed on Monday, local authorities said.

Lian Enqing, 34, made the attack at the No. 1 People's Hospital in Wenling City, Zhejiang Province, in Oct. 2013 after he claimed to be suffering from respiratory problems and discomfort after receiving a nose surgery there in March 2013.

While the hospital confirmed that the surgery was successful, Lian felt he was being cheated by the doctors, according to Lian's sister, Lian Qiao.

From August to Oct. 15, 2013, Lian Enqing was under treatment at Shanghai Mental Health Center, diagnosed with a persistent delusional disorder, his sister added.

But forensics showed Lian was apparently conscious of the attack, meaning he should be held fully accountable for the violent deeds.

Lian was sentenced to death in the first trial by the Intermediate People's Court in Zhejiang's Taizhou City in January 2014. The provincial Higher People's Court upheld the death sentence after he appealed.

Doctor-patient relations in China have been fraught with tension in recent years, as frustration, misunderstanding and dissatisfaction have resulted in violence.

Earlier this year, a doctor and a patient from the central province of Henan died in an elevator shaft following a brawl in a local hospital.