The deaths included three civilians, three police personnel and nine military servicemen while the injured included 10 civilians, two police personnel and one military serviceman, said U Zaw Htay, spokesperson of Myanmar President's Office.
The armed groups -- Arakan Army (AA), Ta'ang National Liberation Army (TNLA) and Myanmar National Democratic Alliance Army (MNDAA) -- launched artillery shells at five places in Mandalay region and Shan state in early hours of Thursday.
In Pyin Oo Lwin of Mandalay region, Defense Services Technological Academy (DSTA) and a toll gate near exit gate of Pyin Oo Lwin town were attacked at about 5:30 a.m. local time.
The simultaneous attacks were also launched at a Gote Twin police outpost, a toll gate, a narcotic checkpoint and a local battalion headquarters in Nawnghkio township on Thursday morning.
As the Gote Twin bridge was blown up, halting the traffic on communication route from Mandalay to Lashio, efforts to construct a double lane Bailey bridge within five days are underway, said the Construction Ministry's release.
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