The four men worked for a ship docking company PT Kodja Bahari, Aria Sofingi, head of the Central Java Search and Rescue Office (Basarnas), remarked here on Monday.
They had worked at the barge's hatch since Sunday morning, July 28, 2019, and did not come out from there until the afternoon.
Several other workers were instructed to look for the four workers, whose bodies were then found in the five-meter-deep hatch.
Their bodies were retrieved from the barge's hatch by officers of the Central Java Search and Rescue Office on early Monday.
The four men were identified as Mardjiono from Bekasi, West Java Province, and Lamani, Nur Huda, and Jadi from Boyolali, Central Java Province.
The authorities are still investigating the source of the poisonous gas that killed the workers.
