Los Angeles city prosecutors are sending letters to 439 medical marijuana dispensaries warning them that they must shut down by June 7, when an ordinance to control pot shops will finally take effect after years of debate and delay. Frank Mateljan, spokesman for the city attorney’s office, said the Police Department and city building inspectors compiled the list of illegal dispensaries. “We’re not saying we have them all,” he said. “This is the initial blanketing of locations that we are aware of at this time.” Under the ordinance, only those dispensaries that registered with the clerk in 2007, when the City Council adopted a moratorium on any new stores, can remain open. City officials estimate that between 130 and 140 of the original 186 registered dispensaries are still operating. Hundreds of dispensaries opened in Los Angeles in the last couple of years as city officials failed to enforce the ban and the City Council struggled to write an ordinance to regulate them. The letters, dated Tuesday, will be sent to both operators and the property owners. They warn that violations of the ordinance are a misdemeanor and could lead to six months in jail and a $1,000 fine. Any stores that stay open in violation of the ordinance could also face civil penalties of $2,500 a day. Asha Greenberg, the assistant city attorney who signed the letter, said, “We’re hopeful that the fact that we’ve given them more than 30 days to comply that a significant number of them will cease operating.” She said dispensaries that do not shut down would face criminal or civil enforcement actions as soon as police verify they were still selling marijuana. At least three lawsuits have been filed that challenge the city’s ordinance and seek injunctions to prevent its enforcement. “They really don’t affect our enforcement right now,” Greenberg said. Greenberg said that the prosecutor’s office would send more letters if residents identify additional illegal dispensaries. “We’re making our best efforts, and we’re using information from really our eyes and ears out there, which is the community,” she said. -- John Hoeffel