Updated from 4:05 p.m. EDTStocks ended flat Tuesday, as some bullish sentiment offset news of a raised terror alert and a case of mad-cow disease in Canada. After going as low as 8417 in late-afternoon trading, the Dow Jones Industrial Average ended the day down just 2 points at 8491. The Nasdaq, which lost nearly 3% Monday, dropped 1 point to 1491. The S&P 500 fell 1 point to 919. Late in the session, the U.S. raised the terror-alert status one notch to orange, or "high risk," based on indications that terror groups are planning attacks in the U.S., or against U.S. interests abroad. Meanwhile, diplomats said more attacks in Saudi Arabia are "imminent," and the U.S. and Britain closed their embassies and consulates for a few days in response, the AP reported. The news sent stocks to lows of the day. Separately, Canadian agriculture officials said they'd discovered the deadly mad-cow disease in a cow that died four months ago and was diagnosed Tuesday. The discovery reportedly prompted the U.S. Department of Agriculture to suspend the importing of Canadian beef, and immediately pressured shares of Dow component McDonald's ( MCD), which dropped 6.4%. "Right now, the market is in a tug of war between the bulls, who think the momentum will carry us up simply because it's the line of least resistance," said Jim Awad, president and market analyst at Awad Asset Management. "The bears are saying the market has come so far, so fast, without ratification from the economy and that the rally has been speculative." Awad said he gives the near-term edge to the bullish camp, especially after Monday's selloff came on such low volume, showing some lack of conviction, while Tuesday's action showed the upward momentum was still there. That said, Awad cautioned that the markets may finally get "a reality check" once companies start warning about second-quarter earnings in mid-to-late June.