Acting Russian Foreign Minister Sergei Lavrov said that there is unverified information that at least six American F-35 jets were “in the Iranian border area” at the time when Iran accidentally downed Ukraine International Airlines flight PS752 last week.

“This information has yet to be verified, but I’d like to underline the edginess that always accompanies such situations,” he said on Friday.

Lavrov said these words to understand the context of the incident, which occurred as Iran was on very high alert after retaliating against Washington’s assassination of Lieutenant General Qassem Suleimani.

His words also mean that Russia might be tracking the surrounding of Iran air space and identifying F-35s.

“There is information that the Iranians were expecting another attack from the United States after the strike but did not know what form it might take,” Lavrov said.

The Russian foreign minister added that he was not trying to excuse anyone for the incident.