Campaigners with Huddersfield group Keep Slaithwaite Special have been collecting objections to plans to demolish Colne Mills on Britannia Road and build an Aldi supermarket.
Their campaign was dealt a blow last week when a fire caused serious damage to the building.
Victoria Minton of Keep Slaithwaite Special said: “We do find the event of this fire disturbing given the controversy and debate surrounding the mill site.
“We’ll certainly be paying close attention to the outcomes of the current investigations being undertaken by both West Yorkshire Fire Service and West Yorkshire Police.”
Fellow campaigner Sarah Jane Mace added: “The sheer amount of support for our campaign shows the strength of feeling against the demolition of this mill to make way for a supermarket.
“If the mill is to be pulled down, that’s a decision to be made through the appropriate channels once the objections have been reviewed. It’s extremely unfortunate that this important decision may now be affected by the actions of an arsonist.”
Campaigners say they are motivated by a concern for the character of the village.
The German-based retailer says it will create 30 full and part-time jobs and create 90 parking spaces for public use.
Critics say it will create traffic congestion and the store will be too large for the village and damage trade at other outlets.