According to an Associated Press report late Tuesday, hundreds were in attendance at the city’s Kiener Plaza earlier in the day to put 1000 white crosses into the ground.

The crosses, the union said, were to honor the memory of the 666 people killed at Patriot, Peabody and Arch Coal operations since 1903.

They also symbolized more than 22,000 active and retired miners and families who will be at risk should the companies eliminate “contractually guaranteed health care benefits,” according to union officials.

Those arrested had been sitting in the street near Peabody's corporate headquarters, the AP said, though it was not known at press time if all of the protestors were still in custody.

The demonstration, though different than the others in symbolism, was the fifth UMWA-led event this year.

The UMWA maintains Peabody Energy and Arch Coal spun off their assets (Arch’s spin-off Magnum Coal was taken over by Patriot in 2008) and deliberately set up Peabody spin-off Patriot to fail so it could shirk its responsibilities to retirees.

Patriot has denied the claim, confirming and reconfirming that the global financial crisis, weak prices and tightened environmental laws were all at the center of its July 2012 decision to file Chapter 11 bankruptcy protection.

Peabody spokesman Vic Svec said earlier this year that the UMWA’s “designed to fail” claims were a “desperate attempt to rewrite history”.

“Patriot was highly successful following its launch more than five years ago, with significant assets, low debt levels and a market value that more than quadrupled in less than a year,” he said, noting Patriot had a bright future and strong balance sheet during that time.

“It is our understanding that when Patriot’s market value was high, the company could have strengthened its financial position.

“Instead, Patriot made a major acquisition of Magnum Coal Company in mid-2008.”

UMWA and Patriot officials did not respond to an ILN request for comment by press time.

The St Louis Business Journal said the union was planning another protest on April 29, which coincides with a US Bankruptcy Court hearing for a motion covering Patriot’s request to cut healthcare benefits.