Hamas militants grab Palestinians suspected of collaborating with Israel, before executing them in Gaza City, August 22, 2014. REUTERS/Stringer

A Hamas militant grabs a Palestinian suspected of collaborating with Israel, before executing him in Gaza City, August 22, 2014. REUTERS/Stringer

A Hamas militant grabs a Palestinian suspected of collaborating with Israel, before being executed in Gaza City, August 22, 2014. REUTERS/Stringer

Hamas militants grab a Palestinian suspected of collaborating with Israel before being executed in Gaza City, August 22, 2014. REUTERS/Stringer

A Hamas militant grabs a Palestinian suspected of collaborating with Israel, before being executed in Gaza City, August 22, 2014. REUTERS/Stringer

Palestinians watch as Hamas militants execute Palestinians suspected of collaborating with Israel in Gaza City, August 22, 2014. REUTERS/Stringer

Hamas militants surround Palestinians suspected of collaborating with Israel before executing them in Gaza City, August 22, 2014. REUTERS/Stringer

A Hamas militant grabs a Palestinian suspected of collaborating with Israel, before being executed in Gaza City, August 22, 2014. REUTERS/Stringer

Palestinians watch as Hamas militants execute Palestinians suspected of collaborating with Israel, in Gaza City, August 22, 2014. REUTERS/Stringer

Hamas militants grab a Palestinian suspected of collaborating with Israel, before being executed in Gaza City, August 22, 2014. REUTERS/Stringer

People watch as Hamas militants surround Palestinians suspected of collaborating with Israel before they executing them in Gaza City, August 22, 2014. REUTERS/Stringer

Hamas militants surround Palestinians suspected of collaborating with Israel, before their execution in Gaza City, August 22, 2014. REUTERS/Stringer

People watch as Hamas militants surround the bodies of Palestinians suspected of collaborating with Israel after they executed them in Gaza City, August 22, 2014. REUTERS/Stringer

Hamas militants surround the bodies of Palestinians suspected of collaborating with Israel after executing them in Gaza City, August 22, 2014. REUTERS/Stringer

Palestinians gather around the bloodstains of Palestinians suspected of collaborating with Israel after they were executed by Hamas militants in Gaza City, August 22, 2014. REUTERS/Stringer