The warplane’s key radar instrument or transponder was switched off, which could potentially have caused an air disaster, Ukraine Today reports.

NATO has been witnessing an abnormal escalation of the Kremlin’s military activity lately, especially close to the Baltic States, with 21 Russian warplanes intercepted in the area last week alone.

See’s video section for more of the latest news from Ukraine in video from Ukraine Today, Ukraine’s 24-hour English-language news channel.