A Ukrainian security official says suspension of transport connections with Crimea is expected to be only a temporary measure.

Ukraine on Friday blocked rail and bus travel between the mainland and the peninsula that was annexed by Russia in March. On Saturday, the Crimean customs service said automobiles also were being blocked at two of the three crossing points on the isthmus leading to Crimea.

Col. Andriy Lysenko, a spokesman for Ukraine's security council, told a briefing Saturday that the train and bus traffic was suspended because "there is a high likelihood of sabotage groups entering under the guise of local people." He said the closure was temporary, but did not say how long it would last.