The list of US companies distancing themselves from the Confederate flag grew on Tuesday, with Sears, Kmart and online marketplace eBay joining Walmart - the world's largest retailer and a staple in the southern US.

"We never want to offend anyone with the products that we offer," Walmart spokesman Brian Nick said in a statement Monday. "We have taken steps to remove all items promoting the Confederate flag from our assortment - whether in our stores or on our website."

The debate over the Confederate battle flag, seen by some as a symbol of Southern heritage but by others as a relic of a racist and shameful era, has taken on a new intensity following the nine murders carried out by Dylann Roof.

Comments by Roof suggested that he drew inspiration from the Confederate flag, as well as white supremacist iconography.

A website apparently created by the accused gunman includes a racist screed and photographs of him holding a Confederate flag and a handgun.

US news reports have said that Civil War enthusiasts - apparently worried that they will soon be unable to buy Confederate symbols - have been snapping up flags and other merchandise online.

Sales of Amazon's most popular Confederate flags rocketed by more than 3,600 percent in just 24 hours, according to the online retailer's website Tuesday.

South Carolina's Republican Governor Nikki Haley led growing bipartisan calls Monday for the removal of the flag from the grounds of the state capitol after the Charleston shooting.

bk/hg (Reuters, AFP)