NEW YORK: Nearly 60 per cent of Americans approve of drone strikes that target extremists in Pakistan, Somalia and Yemen despite concerns that they endanger innocent civilians, a new poll found Thursday.

The Pew Research Center said its national survey showed that 58 per cent approve of US drone strikes against extremists in those countries and that 35 per cent disapprove.

Support for drone strikes crosses party lines, although Republicans, at 74 per cent, are more likely than Democrats, at 52 per cent, to favor the use of drones to target extremists, the poll found.

Read: Drones: choosing between droning on and understanding

Just under half of respondents, 48 per cent, said they were very concerned that drone strikes endanger the lives of innocent civilians, while 32 per cent said they were somewhat concerned.

Only three in 10 Americans said they were very concerned that US strikes could lead to retaliation from extremist groups and only 24 per cent said the strikes could damage America's reputation.

Less than a third, 29 per cent, said they were very concerned about whether the strikes were legal.

US hostage Warren Weinstein and fellow hostage, Italian aid worker Giovanni Lo Porto, were killed in a CIA drone strike targeting an Al Qaeda hideout in Pakistan in January.

Also read: Obama apologises for hostage deaths in Pak-Afghan border strike

President Barack Obama's admission that the strike inadvertently killed the hostages raised fresh questions in America about the limits and risks of the classified, targeted killing program.

Since taking office in 2009, Obama has relied heavily on drone raids to hunt down Al Qaeda leaders and other Islamist extremists from Pakistan's tribal areas to Somalia and Yemen.

Human rights groups and some lawmakers question the legality and the morality of the drone war, citing estimates that hundreds of civilians may have been killed by the strikes.

The survey was carried out between May 12-18 based on telephone interviews with around 2,000 adults living in all 50 US states and the capital Washington.

It has a margin of error of 2.5 per cent.