JAKARTA, Indonesia: Indonesian police said they safely detonated a bomb in a neighborhood on the outskirts of the capital on Saturday after arresting a female would-be suicide bomber and other suspected Islamic militants who were planning to attack the presidential palace this weekend.

The thwarted plot is likely to cause particular concern in Indonesia because of the possibility that women with militant network associations are now being recruited into more active roles, including plotting and carrying out attacks.

“This marks a new chapter of terrorism in Indonesia, where the suicide bombing was to be carried out by a woman,” terrorism analyst Ridwan Habib said in an interview with Indonesian TV.

People living within a 300-meter radius of the boarding house where the pressure cooker bomb was found were evacuated during the police operation.

Two men and a woman were arrested in the neighborhood, said National Police spokesman Boy Rafli Amar. A fourth suspect, a man, was arrested in the central Java city of Solo, said Jakarta police spokesman Argo Yuwono.

The bomb potentially could have caused damage within a wide area, Yuwono said.

Umar Surya Fana, the police chief of Bekasi, a Jakarta satellite city where the neighborhood is located, said the militants were monitored by the police’s counterterrorism squad as they traveled to Jakarta from Solo. The city is known for its radical mosques and Islamic boarding schools.

Police believe the militants were planning to bomb a presidential guard-changing ceremony on Sunday that is a tourist attraction in Jakarta, Fana said.

The woman’s will, which was found during the counterterrorism operation, stated her desire to take part in “amaliyah,” an Arabic term used by extremist groups for attacks or suicide bombings.

“They deliberately chose the target on a Sunday, when many families are hanging out around the national monument and near the palace, with the intention of causing a lot of casualties,” said Habib, the analyst.

Police said those arrested are suspected to be part of a militant network responsible for a bomb-making lab raided last month in West Java province that was operating under the direction of Bahrun Naim, an Indonesian fighting with the Daesh group in Syria.

Those arrested in last month’s raid planned to bomb targets in Jakarta, including the parliament and the Myanmar Embassy.

Muslim-majority Indonesia has carried out a sustained crackdown on militants since the 2002 bombings on the tourist island of Bali by Al-Qaeda-affiliated radicals that killed 202 people. But a new threat has emerged in the past several years from Daesh sympathizers.