Heinz Field crews confirmed they worked alongside first responders to look into the strange situation on Sunday (October 10) following the Steelers' 27-19 win against the Denver Broncos in Week 5.
Responders reportedly focused on the stands and the edge of the field at the Steelers' home stadium on Sunday.
The Steelers also confirmed they are aware of the situation, which they do not condone and are working with local authorities to obtain more information.
It is illegal to spread ashes anywhere without the property owner's permission in the Commonwealth of Pennsylvania and Steelers officials said fans are not permitted to do so at Heinz Field, CBS Pittsburgh reports.
The incident remained under investigation as of Monday (October 11) morning.
The Steelers earned their second victory of the 2021 NFL season on Sunday thanks to big performances from veteran quarterback Ben Roethlisberger and rookie running back Najee Harris.
Roethlisberger threw a 50-yard touchdown pass to Diontae Johnson on the Steelers' opening drive and connected with Chase Claypool for a second touchdown pass in the third quarter.
Harris provided Pittsburgh's second touchdown of the first quarter on a one-yard run, while recording a career best 122 yards on 23 rushing attempts.
The Steelers will host the Seattle Seahawks next Sunday (October 17) at Heinz Field during the Week 6 Sunday Night Football matchup.