KITCHENER -- City staff in Woodstock, Ont., are investigating after tacks, needles and nails were found at a city park on Monday, including some around the play equipment.

It's a troubling case of déjà vu, as this incident is one of about a half-dozen to happen in Woodstock over the summer.

One of the most recent ones happened at Southside Park. The Woodstock Police Service says it was reported at around 7 a.m. on Monday after staff found more tacks and needles in the mulch and sandbox there.

While crews cleaned the area, a suspicious male was seen in the area. He was reportedly wearing dark clothes, a hoodie and a black backpack. He was seen smoking and had long, shaggy brown hair that was slicked back. He was unshaven.

At around 12:30 p.m. that day, police got a report that thumbtacks were found around a school yard and playground on Hunter Street. Then, about four hours later, parks staff found about 10 sewing needles under a "spider web climber."

Officials are asking parents to do a thorough inspection of any playground spaces before they let their kids play.

Back in August, a similar incident happened at the same park. A mother and daughter were playing on the playground when they found something sharp. City staff arrived and ended up collecting hundreds of thumbtacks and sewing needles.

That wasn't the first instance, either.

"This is the second act of vandalism in Southside Park with intent to injure," a Facebook post from the city last month read in part. "Earlier this month, Woodstock Police were also called to investigate the spread of nails throughout the cricket pitch and nearby playing area."

The city closed the parks, and crews arrived with magnets to collect the sharps.

Parks Supervisor Reta Horan told CTV Kitchener at the time that the city would be upping its checks on the park, ensuring that city staff would be checking parks as often as they can.