MANILA, Philippines -- Philippine President Rodrigo Duterte, who is best known for his deadly war on drug dealers, says news that his daughter is pregnant with triplets inspires him to carry on his tough-guy crusade.

Daughter Sara Duterte-Carpio issued a statement Friday saying she is seven weeks' pregnant with triplets. Duterte-Carpio, 38, who was recently elected mayor of Davao city, already has two children with her lawyer husband Manases Carpio. She revealed her pregnancy in explaining why she felt she was not in shape to take part in "merrymaking" at her city's annual Kadayawan Festival this month.

Philippine media reported that Duterte said he is "delighted" to hear of his daughter's pregnancy.

"He is also hopeful that she will be able to see through the pregnancy smoothly and well," he said in a statement issued through Communications Secretary Martin Andanar. "He hopes to leave a legacy of a Philippines that is safe from crimes and drugs to the future generation of Filipinos."

According to the national police count as of last week, more than 500 people have been killed in gunfights with police and nearly 8,000 have been arrested in the government's war on drugs since Duterte took office at the end of June. Local media and other groups have higher tallies, some nearly 1,000, and say they include apparent victims of summary killings.