Sri Lanka's parliament has agreed to extend a state of emergency for one month following the assassination of the country's foreign minister.
Sri Lankans have regularly lived under states of emergency
Under the state of emergency, police and the military have more powers to conduct searches and detain people.
The bill was passed overwhelmingly due to the support of the main opposition party.
The government blames Tamil Tigers for the assassination on Friday, but the group has denied responsibility.
"There can be no room for murder, intimidation, extortion and child conscription and therefore we need to bring a strong legal framework in order to investigate these crimes," National Security minister Ratnasiri Wickremenayake told parliament while introducing the bill.
As well as allowing the detention of suspects without charge and searches without warrants, the emergency legislation also gives the president powers to make laws, ban public gatherings and to censor the media.
None of the additional powers have so far been used.
The legislation was passed by 124 votes to 21.
The support of the opposition United National Party (UNP) was crucial for its passage.
Police have increased powers under a state of emergency
President Kumaratunga's Sri Lanka Freedom Party has not had a majority in parliament since June when the Sinhala nationalist People's Liberation Front, or JVP, left the government in protest at a deal struck with the Tamil Tigers over tsunami aid.
"We support the emergency on the basis it will be used only for this investigation and not against political opponents," a UNP spokesman told AFP news agency.
President Kumaratunga last declared a state of emergency in November 2003 saying that the then UNP government led by Ranil Wickramasinghe had made too many concessions to the Tamil Tigers.
She lifted the emergency after Wickramasinghe returned to Sri Lanka from a trip to the US.
The SLFP won subsequent elections in April 2004, but without sufficient seats to form a majority.
The Tamil Tigers have been fighting for a separate homeland in the country's north and east since 1983.
More than 60,000 people died in the war before the ceasefire agreement.