Port Elizabeth - A Port Elizabeth fisherman was missing on Sunday after he apparently went overboard from his boat, the National Sea Rescue Institute (NSRI) said. “The fisherman may have gone overboard without a life-jacket,” said NSRI spokesperson Craig Lambinon. Rescue crews were alerted to the incident around 05:00 on Sunday, after the other fishermen aboard the vessel – located three nautical miles off-shore the Port Elizabeth port – noticed their colleague was missing. “The fisherman may have gone overboard in the early hours of the morning.” A sea rescue craft and helicopter were involved in an extensive search for the man throughout the day – but no sign was found. All life-jackets aboard the vessel were accounted for. Police have opened an investigation and on Sunday afternoon, a diving unit was still conducting a search.