By Sara Sjolin, MarketWatch

LONDON (MarketWatch) -- Europe's stock markets showed broad-based gains on Thursday as investors largely ignored a mixed bag of purchasing managers indexes from the region and instead used recent market weakness as a buying opportunity.

"Markets have developed a remarkable ability to shrug off the bad and have needlelike focus on the positive," said Jonathan Sudaria, dealer at London Capital Group, in a note.

The Stoxx Europe 600 index is down 0.8% over the past three months, largely due to geopolitical issues in Ukraine, Iraq and Gaza. Peter Dixon, strategist at Commerzbank, said Thursday's move higher was more due to an unwinding of the "collapse" we saw in late July and early August rather than a bright view of the future. Read: Russia-exposed stocks tank 15% since start of Ukraine conflict

"There is definitely an underlying story, which is the euro zone losing some momentum. It will play a much bigger role in investors' thinking in September," he said.

Data: The PMIs coming out of Europe were mixed. The readings for the overall euro zone missed expectations, with particularly the manufacturing sector showing signs of weakness. Activity at the currency union's factories remained in expansion territory at 50.8 in August, which, however, was a 13-month low. A reading above 50 indicates expansion.

Germany's PMIs actually surprised to the upside, although they slipped from July. The story was more mixed in France, where the services PMI climbed to a five-month high, but the manufacturing PMI tanked to a 15-month low.

In China, HSBC's manufacturing PMI showed factory activity in the world's second largest economy weakened to a three-month low in August, sending miners listed in London lower. Mining firms are sensitive to weakness in China's industrial sector, as it is a major user of natural resources.

Market reaction: The Stoxx Europe 600 climbed 0.7% to end at 337.51, marking the highest closing level since late July. Read: Raiffeisen rallies, miners slip: Europe movers

Germany's DAX 30 index gained 0.9% to 9,401.53, while France's CAC 40 index picked up 1.2% to 4,292.93. The U.K.'s FTSE 100 index added 0.3% to 6,777.66. Read: Miners drop in London after weak China PMI

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