Sector North In the Ogulin area of the HV Karlovac Corps AOR, the 99th Brigade, reinforced by the 143rd Home Guard Regiments Saborsko Company, moved towards Plaški at 5 a.m., but the force was stopped and turned back in disarray by 6 p.m. The 143rd Home Guard Regiment advanced from Josipdol towards Plaški, encountering minefields and strong ARSK resistance. Its elements connected with the 14th Home Guard Regiment, advancing through Barilović towards Slunj. Near the city of Karlovac, the 137th Home Guard Regiment deployed four Reconnaissance around midnight of 3&ndash;4 August, followed by artillery preparation and crossing of the Korana River at 5 a.m. The advance was fiercely resisted by the ARSK 13th Infantry Brigade, but the bridgehead was stable by the end of the day. The 110th Home Guard Regiment, reinforced by a company of the 137th Home Guard Regiment, advanced east to the road leading south from Karlovac to Vojnić and Slunj, where it met heavy resistance and suffered more casualties to landmines, demoralizing the unit and preventing its further advance. In addition, the attached company of the 137th Home Guard Regiment and the 104th Brigade failed to secure the regiments flanks. The 104th Brigade tried to cross the Kupa River at 5 a.m., but failed and fell back to its starting position by 8 a.m., at which time it was shifted to the bridgehead established by the 110th Home Guard Regiment. A company of the 99th Brigade was attached to the 143rd Home Guard Regiment for operations the next day, and a 250-strong battlegroup was removed from the brigade and subordinated to the Karlovac Corps directly.
Question: How many hours after the 137th Home Guard Regiment deployed four Reconnaissance did they cross the Korana river?
Answer: 5