TAIPEI (Taiwan News) — Police are investigating death threats made against DPP Caucus Leader Ker Chien-ming (柯建銘) and his family on Thursday.

DPP Caucus Secretary-General Wu Szu-yao (吳思瑤) said police were told of the threats and began investigating on Friday, per Yahoo News. Wu said Ker had received an email in which the author threatened to shoot Ker, his wife, and children within a month.

Wu said the email contained detailed personal information about Ker and his family, which was also sent to other DPP legislators. She said Ker’s Hsinchu office also received a handwritten letter with threatening messages on Thursday.

Wu said threats are unacceptable and will fail to deter actions to safeguard democracy. She added that any action to mobilize society in a democratic nation should be respected.

Ker is a founding member of the DPP and was first elected to the legislature in 1992. He has been a legislator for 10 terms, representing Hsinchu and New Taipei.