UPDATE 1-Indonesia's March tin exports jump 37.6 pct -ministry

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JAKARTA, April 13 (Reuters) - Indonesia's refined tin exports rose 37.6 percent in March from the same month last year as smelters increased shipments to benefit from high prices and as rains eased, an official at the trade ministry said on Wednesday.

Indonesia, the world's top tin exporter, shipped 9,051.46 tonnes of refined tin in March, compared to 6,576.01 tonnes in March last year, trade ministry data showed.

"The weather is improving and tin prices are also high, which helped smelters step up production," said Junaedi, the head of the export of mining products at the ministry.

Smelters may also process tin slag to produce more refined tin, he added.

Tin shipments to Japan tripled in March to 304.64 tonnes despite the evastating tsunami and earthquake from 95.37 tonnes in February, data showed.

However, smelters said on Monday that the supply of tin ore to independent smelters in Bangka island, the country's main source of tin, had fallen as rain and police raids on illegal miners had hampered mining.[ID:nL3E7FB1EM]

The police have confiscated 72 tonnes of illegal tin ore on the island, Juwari, the South Bangka police chief, said on Wednesday.

Smelters expect tin production to fall in coming weeks because of tight raw material supplies as small-scale traditional miners cut back on activity to avoid police raids.

A crackdown on illegal mining, tighter export regulations, declining onshore reserves and rain that has hindered production in Indonesia have helped drive the tin rally. .

Indonesia expects to produce 90,000 tonnes of refined tin this year, up from 78,965 tonnes in 2010. (Reporting by Yayat Supriatna; Additional reporting by Dwi Sadmoko in Pangkal Pinang; Writing by Fitri Wulandari; Editing by Alan Raybould)