This is partially true. According to ABC News, the U.S. intercepted four Russian aircrafts after they failed to identify themselves after nearing Alaskan airspace. This included two bombers. None of these aircrafts entered U.S. or Canadian airspace, and they had no plans to do so. Because of the nature of Eastern Russia being near Alaska, it is not uncommon for planes to be near Alaskan airspace. There was no evidence of these bombers dropping any objects.
https://abcnews.go.com/US/us-intercepts-russian-bombers-off-alaska-2-straight/story?id=97260923