A nearby resident said they heard screaming and crying and watched people running off the property, one wearing a mask, before they sped away in two vehicles, the Nelson App reports.
Another woman said she heard a single gunshot around 1.15pm.
Police continue to appeal for witnesses who may have seen anything in the Washington Rd area on Tuesday from 12.45pm to 1.30pm.
"The investigation team would also be interested in hearing from people who have any CCTV footage of Washington Rd."