Wall Street and key European equity markets rose on Friday in thin US holiday weekend trading, with a key US exchange suffering an outage.

Trading on the Chicago Mercantile Exchange, one of the world's major operators, was halted by a technical outage first reported at 0240 GMT Friday.

"Due to a cooling issue at CyrusOne data centers, our markets are currently halted," the CME said in a statement.

"All CME Group markets are open and trading," it said in a later statement.

Market participants rely heavily on CME platforms to manage risk through futures contracts tied, for example, to stock indices, interest rates and currencies.

The outage also froze pricing on the US benchmark crude contract, WTI, for several hours.

"It's been a while since we've had such a long outage," said Neil Wi

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