A Spanish F-18 fighter and a Russian Su-27 were involved in a tense encounter over the Baltic Sea on Tuesday, as seen in a video released by Russia’s Defense Ministry.

The Spanish F-18 took makes part of NATO’s Baltic Air Policing mission and took off from the Lithuanian base of Siauliai. It is believed that is was tagging a plane that was reportedly carrying Russian Defense Minister Serguéi Shoigu, who was returning to Moscow from the Russian enclave of Kaliningrad.

The F-18 then was encountered and forced away by two Su-27 escort jets, when the incident occurred.

The Russian news agency TASS reports that the Russian plane was over international waters; El Pais reports that the Russian aircraft was flying near the Alliance’s airspace – Lithuania and Poland – without a flight plan or IFF identification.

The Spanish Defense Ministry did not comment on the incident, while a NATO spokeswoman confirmed that a Russian plane was tracked over the Baltic on Tuesday, without making any specific reference to the incident.