MEXICO CITY, Dec. 24 (Xinhua) -- The governor of Mexico's central state of Puebla, Martha Erika Alonso, and her husband Rafael Moreno Valle, ex-governor of the state, were killed in a helicopter crash on Monday, the head of the National Action Party (PAN) Marko Cortes confirmed.

Alonso and her husband, who was now serving as a senator, were both members of the PAN.

"I deeply regret the fatal accident in which Martha Erika Alonso, Rafael Moreno Valle and others lost their lives. May they rest in peace," Cortes posted on Twitter.

Mexican President Andres Manuel Lopez Obrador also expressed his condolences and pledged to investigate the causes of the crash in a Twitter message.

"As the authority, I am committed to investigating the causes; saying the truth about what occurred and acting accordingly," said Lopez Obrador.

Mexico's Civil Protection agency said the crew were also killed.