The crime branch of Mumbai Policeon Wednesday arrested a 34-year-old woman under the Essential Commodities Act for hoarding a huge quantity of masks for sale in black market, an official said.Masks are in high demand currently because of the coronavirus outbreak.Unit-10 of the crime branch seized some 90,000 masks worth Rs 22.50 lakh from Rinku Tayyil, a resident of suburban Bandra, he said.On March 28, the police had arrested five persons and seized 2.97 lakh masks worth Rs 74.90 lakh, he said.During the probe it came to light that Tayyil was in contact with one of them, he said, adding that further probe was on.