What were Iranians looking for on the ship ‘Wila’?

Iran’s use of military forces to board the commercial vessel in international waters constituted a blatant violation of international law, the IMSC said. But the Wila didn't call for help.

This picture released by the U.S. Navy allegedly shows a ship of the Iranian Navy and members of the Iranian forces boarding civilian tanker WILA en-route to the UAE, in international waters in the Strait of Hormuz, August 12, 2020. Picture taken on August 12, 2020 (photo credit: US NAVY/HANDOUT VIA REUTERS)
This picture released by the U.S. Navy allegedly shows a ship of the Iranian Navy and members of the Iranian forces boarding civilian tanker WILA en-route to the UAE, in international waters in the Strait of Hormuz, August 12, 2020. Picture taken on August 12, 2020
(photo credit: US NAVY/HANDOUT VIA REUTERS)
US Central Command observed Iranian forces, including two ships and an Iranian Sea King helicopter, board a ship called "Wila" on August 12. The International Maritime Security Construct (IMSC) said it had “monitored an incident involving Iranian forces who boarded a tanker in the international waters of the Gulf of Oman near the Strait of Hormuz.”
At the same time, the US revealed it had confiscated a million barrels of Iranian gasoline from four ships heading to Venezuela. Was the Wila incident connected? Samir Madani, co-founder of Tanker Trackers suggests the explanation may be more complex than it appears.
Let’s start with what we know. Iran’s use of military forces to board the commercial vessel in international waters constituted a blatant violation of international law, the IMSC said. It now turns out that the Wila did not call for help.
Sentinel, which is the Coalition Task Force (CTF) aspect of the IMSC, said its mission is to deter and expose this malign activity and reassure the maritime community. A coalition ship was providing overwatch during the incident.
So what happened with the M/T Wila ship? The ship was on the way to Khor Fakkan, a UAE port in the Gulf of Oman. At around 8:30 p.m. the Coalition warship saw the Iranian Navy SH-3 Sea King helicopter approach and armed men rope down.
Could this be Iran hijacking a ship? Iran has done this before. In July 2019 Iran did the same thing with a British tanker. The Gulf Sky ship also disappeared in July off the UAE and ended up off the coast of Iran with the crew claiming they were hijacked. 
Samir Madani, co-founder of the group Tanker Trackers, says that the explanations put forward for what Iran was doing with the Wila does not add up. Some have suggested Iran boarded the ship in retaliation against the US seizing Iranian gas from four tankers bound or Venezuela.
Others said the Wila’s interdiction was linked to the UN vote that saw an arms embargo not extended. But that doesn’t make sense Madani notes. Why would you cause a maritime incident during the vote, a vote Iran was sure to win? It would add fuel to the US campaign to extend the embargo. It’s not logical that Iranians roped down to a ship and then realized the optics looked bad, he says.
It also does not make sense Iran was retaliating to steal the ships oil back or hold it to get its gasoline back from the US. Iran did this last year with the British tanker in retaliation for the interdiction of its tanker that was heading to Syria. This time the Iranians left quickly.
Madani suggests that the IRGC boarded the vessel to confiscate recording devices to find out where the four vessels full of gasoline were. If Iran’s gas had gone missing it would want to know what was going on with the ships. Those ships carrying gas to Venezuela were not Iranian but contracted through Greece. 
Hellenic Shipping News says that M/T Wila is managed by the same Greek-based group that appears linked to the four ships moving Iranian gasoline to Venezuela. “In targeting the vessel, Iran has potentially sought to send a clear message to vessels which decide to renege on their willingness to partake in, or facilitate economic activities linked to the nation.” But Iran didn’t hold the ship, indicating they may have just been looking for information. The full story continues to be unclear.