(CNN) -- Bulgarian police have widened their investigation into last week's bombing attack on Israeli tourists to towns near the border with Romania, asking hotels for surveillance video that might have captured the suspected bomber. Hotels in the Black Sea coastal city of Varna say police have been asking for video showing a particular suspect and are giving a sketch of the suspect to management. Investigators also have questioned workers at a car rental agency near the Black Sea coast where the man attempted to rent a car before Wednesday's attack, the agency's owner told CNN. Five Israeli tourists were killed and more than 30 other Israelis were wounded when a suicide bomber blew apart their bus at Burgas International Airport.
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Police are asking hotels for surveillance video
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The suspect was also seen at a car rental agency
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Five Israelis were killed in a suicide bombing last week
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Authorities don't rule out the possibility of a second suspect
@placeholder authorities still have not been able to identify the bomber, who was seen on airport security videos about an hour before the attack.