(Updates with more earnings details)

MEXICO CITY, April 29 (Reuters) - Mexican metals miner and railroad operator Grupo Mexico said on Tuesday its first-quarter profit fell 34.8 percent compared with the same period a year earlier as an increase in production failed to offset steep falls in metal prices.

The company reported a profit of $376.54 million in the three months to end-March.

Revenue fell 11.2 percent to $2.18 billion.

Grupo Mexico noted metals prices fell during the quarter from the year-ago period, with silver down 32 percent, gold down 21 percent and copper down 10 percent.

The company's production of copper, which accounts for 82 percent of Grupo Mexico's mining division revenue, increased 5 percent compared with the year-earlier period.

Shares in Grupo Mexico closed up 2.1 percent on Tuesday at 39.8 pesos per share before the company reported its results.

(Reporting by Christine Murray and David Alire Garcia; Editing by Ken Wills)