Chile's government said it will tighten security to avoid an escalation in violence after the most serious bomb attack the country has suffered in decades left 14 wounded on Monday.
The government has called the act a "terrorist attack," although no group has claimed responsibility and authorities have yet to identify those responsible.
The blast occurred near a metro station in the affluent residential and shopping neighborhood of Las Condes at Monday lunchtime.
President Michelle Bachelet interrupted her planned schedule to call a high-level security cabinet meeting on Tuesday.
The attack was the worst that Chile, one of Latin America's most stable countries, has suffered since it returned to democracy in 1990 after a seventeen-year dictatorship.
This week Chile commemorates the 41st anniversary of the 1973 military coup that removed socialist President Salvador Allende from power. The events of the coup still deeply divide Chilean society, and the anniversary is traditionally a time of protests that often turn violent.
"It is foreseeable that people might get carried away with this type of thing ... we are going to increase security with all the tools we have on hand, which in this case is the police force and detectives," said Interior Undersecretary Mahmud Aleuy.
Aleuy said authorities have identified 38 possible locations that could be at risk during the coup's anniversary on Thursday.
The bomb was a homemade device made with a fire extinguisher filled with gunpowder and stopwatch, according to the public prosecutor. Police have a security video of two people placing the device in a trash can before fleeing in a car.
A number of explosive devices have been planted close to banks and police stations in Chile in recent years.
In the past, one member of an anarchist group has been killed and another injured trying to set off explosive devices, but no bystanders have been hurt.