Jakarta , Indonesia ( CNN ) -- Indonesia is on high alert after police foiled terror plans to detonate bombs Friday near a church in a Jakarta suburb . The plan was to detonate the bombs by a timer , using a mobile phone , just before a scheduled Easter service at a Catholic church in Tangerang , authorities said . Police uncovered the plan after the arrests of 19 suspects over the past few days . The suspects were allegedly involved in the foiled attack near the Catholic church . Authorities found about 150 kilograms ( 330 pounds ) of explosives near the church on Thursday , said Boy Rafli Amar , the national police spokesman . There were two large bombs and five smaller ones , he said . `` Starting tonight until the day after Easter , the military and the police will be on the highest alert at all places , '' said Joko Suyanto , the coordinating minster for security . Indonesia is a predominantly Muslim nation , but has other religious minorities such as Christians and Hindus . The government has been vigilant over the threat of sectarian violence . Security will be beefed up around houses of worship , tourist destinations , embassies and sites visited by foreigners , officials said . Police arrested the suspects in connection with the church bomb and/or attempted mail bomb attacks last month . The mail bombs were packed as fake books and sent to four targets , including a moderate Muslim scholar and a human rights activist , officials said . Two security officials and a police detective were injured while attempting to defuse one of the mail bombs , the police spokesman said . Indonesia has been on edge after last month 's parcel bombs and the Friday suicide bombing in a mosque in Cirebon , West Java .
Authorities found about 150 kilograms ( 330 pounds ) of explosives near a church . Police arrest 19 allegedly tied to either the church bomb or mail bombs . There 's a Christian minority in the largely Muslim nation .