By Ray Sanchez, CNN

The new governor of the Mexican state of Puebla and her politician husband were killed Monday in a helicopter crash in central Mexico, according to the head of their political party.

President Andrs Manuel Lpez Obrador also confirmed the deaths on Twitter Monday evening. He offered his condolences to the families of Martha Erika Alonso and husband Rafael Moreno Valle, and vowed a transparent investigation into the cause of the Christmas eve crash.

Marko Cortes, head of the center-right National Action Party, said via Twitter he was deeply saddened to hear about the accident in which Alonso, Moreno and others were killed.

"We are in mourning," he wrote.

Alonso assumed the governorship of the east-central Mexican state on December 14 after narrowly defeating her opponent. She was the state's first female governor.

Moreno was a senator, and governor of Puebla from 2011 to 2017.

Lpez Obrador had tweeted earlier Monday that he had received information about the crash and was trying to confirm that Alonso and Moreno was on board.

On Twitter Sunday evening, Alonso offered good wishes for the holidays to the families of Puebla and said the coming year could be peaceful and prosperous despite the great challenges facing the state.

Lpez Obrador said via Twitter that his government investigation of the crash will "tell the truth about what happened and act accordingly."