Police - including armed officers - cordoned off the area while a search took place.
Police took two people into custody and were still conducting inquiries.
"It will be some time before details such as whether the two people in custody will face charges and if so, for what.''
Meanwhile, earlier in Hastings on Friday two people were detained after security officers found ammunition when a group tried to enter Hastings District Court.
A Ministry of Justice spokeswoman said two items of ammunition were found in a person's jacket during routine screening. A woman in the same group was found with drug paraphernalia.
"The police attended and dealt with the matter," the spokeswoman said.