In peaceful circumstances, they are usually installed by the police or road transport authorities; they are also commonly employed during wars and are usually staffed by heavily armed soldiers in that case. During protests and riots, both police and demonstrators sometimes use roadblocks.
Roadblock in the West Bank
Polish barricade during the Warsaw Uprising (1944)
Roadblock during roadworks at Hisingen, Sweden, 2013
- Who Approves of Those Who Block Roads to Protest in the Americas? http://www.vanderbilt.edu/lapop/insights/IO921en.pdf
- Clearing the Path for Land Rights, One Road Block at a Time: How Peru's Indigenous Population can Assert Their Land Rights Against Peru's Government, 1 Global Bus. L. Rev. 229 (2010-2011)
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