US STOCKS-U.S. stocks choppy in early trade on mixed economic data

(Corrects to "stocks" from "stock" in headline and first paragraph)

* April construction spending up, consumer spending flat

* Manufacturing picks up in May

* Intel (Swiss: INTC.SW - news) falls on Altera (NasdaqGS: ALTR - news) buy, weighs on S&P, Nasdaq

* Cancer drug maker's jump after data presentation

* Indexes down: Dow 0.05 pct, S&P 0.16 pct, Nasdaq 0.42 pct

By Tanya Agrawal

June 1 (Reuters) - U.S. stocks were choppy in early trading, giving up their gains from a strong opening, as investors digested a slew of data that sent a mixed picture on the pace of the economy's recovery.

Data from ISM showed the pace of manufacturing growth rose in May. Other data showed construction spending surged in April, but consumer spending was unexpectedly flat.

The data left investor's with mixed thoughts about the strength of the economy's recovery and, ultimately, when the Federal Reserve will raise interest rates.

Boston Fed President Eric Rosengren said Monday that he would like to begin raising rates as soon as possible, but risks from the slowdown in China and Europe in particular loom large even as growth at home is still not strong enough.

At 10:17 a.m. ET the Dow Jones industrial average was down 9.71 points, or 0.05 percent, at 18,000.97, the S&P 500 was down 3.3 points, or 0.16 percent, at 2,104.09 and the Nasdaq Composite was down 21.34 points, or 0.42 percent, at 5,048.69.

Nine of the 10 major S&P indexes were lower, with the utilities index the only one in the black with a 0.36 percent rise.

Intel shares fell 2 percent to $33.76 and were the biggest drag on the S&P and the Nasdaq after the company agreed to buy programmable-chip maker Altera for $16.7 billion. Altera rose 6.1 percent to $51.83.

OM Group (NYSE: OMG - news) jumped 27 percent to $33.75 after Apollo Global Management agreed to buy the magnet and battery maker for $1.03 billion.

Citigroup (NYSE: C - news) was up 1.2 percent at $54.73 on a Wall Street Journal report that the bank is expected to close its troubled Banamex USA unit. Goldman Sachs (NYSE: GS-PB - news) upgraded the stock to "buy" from "neutral".

Immunogen (NasdaqGS: IMGN - news) surged 51 percent, while Oncothyreon jumped 18 percent, leading a rise in cancer drug makers' stocks after they presented positive data at a conference.

Molycorp (NYSE: MCP - news) fell 15 percent to 45 cents after it missed an interest payment, heightening concerns that the struggling rare earths miner could file for bankruptcy before the end of the month.

Declining issues outnumbered advancers on the NYSE by 1,685 to 1,163, for a 1.45-to-1 ratio on the downside. On the Nasdaq, 1,726 issues fell and 808 advanced for a 2.14-to-1 ratio favoring decliners.

The S&P 500 index showed nine new 52-week highs and five new lows while the Nasdaq recorded 59 new highs and 22 new lows. (Editing by Savio D'Souza)