West Jakarta Mayor Burhanuddin has called for premarital sex between teenagers in big cities to be combated by building more mosques and educating youths on matters of religion and morality.

According to the city's official news portal Beritajakara.com, Burhanuddin quoted results of a 2010 study by the Indonesian Commission for Child Protection (KPAI) that said 32 percent of youths aged 14-18 in cities like Jakarta, Bandung and Surabaya were sexually active.

"The results of that study have raised great concern. This is why the presence of mosques and sufficient religious studies are expected to strengthen the faith of students and minimize negative activities," Burhanuddin said.