Russian air force planes dropped a 25-kg (55-lb) sack of cement on a suburban Moscow home last week while seeding clouds to prevent rain from spoiling a holiday, Russian media said on Tuesday.
"A pack of cement used in creating ... good weather in the capital region ... failed to pulverize completely at high altitude and fell on the roof of a house, making a hole about 80-100 cm (2.5-3 ft)," police in Naro-Fominsk told agency RIA-Novosti.
Ahead of major public holidays the Russian Air Force often dispatches up to 12 cargo planes carrying loads of silver iodide, liquid nitrogen and cement powder to seed clouds above Moscow and empty the skies of moisture.
A spokesman for the Russian Air Force refused to comment.
June 12 was Russia Day, a patriotic holiday celebrating the country's independence after the break-up of the Soviet Union.
Weather specialists said the cement's failure to turn to powder was the first hiccup in 20 years.
The homeowner was not injured, but refused an offer of 50,000 roubles ($2,100) from the air force, saying she would sue for damages and compensation for moral suffering, Interfax said.