The deceased were the members of the marine unit who were training in Gaza's waters, informed a text message sent to the reporters in Gaza. The message also said that more details would be obtainable at a press conference later Monday, Jun 7.
The Israeli militants said that it stopped the attack on targets in Israel, but was not ready to give further details.
Israeli media informed that helicopters were involved in the attack.
Al-Aqsa Martyr's Brigade, a Palestinian militant group, claimed that the four men were members of its marine unit who were training at sea.
The Palestinian naval police said two people were still missing.