This is the best summary I could come up with:

Global Positioning System (GPS) disturbances detected across NATO member Poland on Tuesday have sparked speculation of Russian involvement, following a similar incident in the region this month.

Polish news outlet Radio Zet portal reported "over northern and central Poland, the GPS signal was again jammed," with Warsaw, Łódź, Tricity and Olsztyn among cities affected and that Swedish military intelligence agency MUST was investigating the cause.

Earlier in January, GPS jamming was detected in eastern and southeastern parts of NATO's newest member Finland, which Jukka Savolainen from the country's Hybrid Competence Center said may have been "intentionally caused or by-products" of Russia's activities.

While there is no proof of Moscow's involvement, the incident followed growing tensions between Finland and Russia due to the former's accession to the alliance and Helsinki's closer ties with the U.S. military.

Gpsjam.org organizer John Wiseman noted the significance of the Russian Ministry of Defense announcement of an electronic warfare (EW) exercise with the Baltic Fleet based in Kaliningrad in December, days before jamming around the region increased.

The post was shared by journalist Euan MacDonald, who wrote: "A Russian jammer in Kaliningrad can cause widespread disruption to GPS signals.

The original article contains 480 words, the summary contains 193 words. Saved 60%. I'm a bot and I'm open source!