Panaji, July 17 : Amid a three-day lockdown in Goa from Friday, clamped by the state government in view of the sustained spike in Covid-19 cases, the opposition here has questioned the movement of trucks carrying iron ore in the state's hinterland. "Ore transportation from Sirsai to Amona via Sanquelim during #lockdown today! Is this possible without collusion from (the) very top of political leadership & that of the state administration?" tweeted Goa Forward party president and MLA Vijai Sardesai on Friday, while posting a video of the truck movement. A government spokesperson said that movement of iron ore had been deemed as an "essential service" as a result of which its transportation during lockdown was a legal activity. Medical services, essential services and industries and their respective workforce have been exempted from the lockdown. Meanwhile, public movement was down to a minimum in the major towns and the state capital on account of the lockdown on Friday. "We are looking to restrict public movement. The Police Control Room vans are making announcements via public address systems urging people to stay indoors in most areas," Superintendent of Police (North Goa) Utkrisht Prasoon told reporters. "We have observed very little movement throughout the state, including in the coastal areas," the official also said. The lockdown will be in place till Monday morning, after which the state will follow a night curfew from 8 p.m. to 6 a.m. till August 10. The state has witnessed a spike in Covid-19 cases in the recent weeks, with the tally of active cases crossing 1,000. /IANS