Units of the Belarusian and Russian armies practiced repulsing an enemy assault followed by counterattacking in the Borisovsky exercise area. Ground troops and Air Force units were involved. Close attention was paid to the organization of interaction between army units at all levels. The Belarusian-Russian strategic army exercise Zapad 2017 began on 14 September to end on 20 September. Some 12,700 military personnel are taking part in the Zapad 2017 exercise. About 10,200 personnel are deployed in Belarus (slightly more than 7,000 people from Belarus and about 3,000 troops from Russia). The Belarusian part of the exercise will also involve a total of 370 armored vehicles, including about 140 combat tanks. Up to 150 artillery units and multiple-launch rocket systems, over 40 aircraft and helicopters will be deployed as well.