Authorities in Mexico State said that an Institutional Revolutionary Party legislator was killed by an assailant on Sunday, the second politician from that party slain in the past two days.

Jaime Serrano Cedillo, a 45-year-old state deputy, was killed in Nezahualcoyotl, a district that borders Mexico City, the state Attorney General's Office said in a statement. No motive was given for the attack.

Local media reported that he was stabbed in the chest as he walked down a street and was rushed to the hospital by his family, but later died. The assailant fled and no arrests have been made.

Mexico State's PRI Gov. Eruviel Avila Villegas condemned Serrano's killing on his Twitter account and called for an investigation.

Serrano was the second politician from that party killed in the past two days.

On Friday, Eduardo Castro Luque, a PRI deputy-elect in Sonora's state legislature, was shot dead outside his home in Ciudad Obregon two days before he was to take office. Two assassins fled the scene on a motorcycle.

The 48-year-old owned a publicity agency and was the operating manager of the Yaquis professional baseball team in Ciudad Obregon.

In August, the mayor-elect of the town of Matehuala in San Luis Potosi state was also shot to death. He also belonged to the Institutional Revolutionary Party.

"We need a state of law to protect us, to give us security and certainty. We need justice and to live under the protection of the law," said Cristina Diaz Salazar, secretary-general of the PRI's National Executive Committee, on Sunday in response to Castro Luque's death.

Authorities have suggested no link between the killings.

The politicians belonged to same party as President-elect Enrique Pena Nieto whose victory in the July 1 presidential election has been questioned by losing candidate Andres Manuel Lopez Obrador.