A federal official says a laptop found in the Las Vegas shooter's hotel suite after the deadliest mass shooting in modern U.S. history was missing a hard drive.

The official says Wednesday that investigators believe gunman Stephen Paddock removed the hard drive from the laptop before taking his own life after he opened fire on a crowd at a country music festival. The official said the hard drive hasn't been found.

Investigators haven't determined what led Paddock to open fire on the crowd, killing 58 people and injuring hundreds of others on Oct. 1.

Meanwhile, Officials have projected the cost of emergency police, fire and other services involving the Las Vegas massacre at about $4 million.

The disclosure Wednesday came after pledges by the federal government to provide $1 million, and from the state of Nevada to offer $600,000 to defray the costs involving the Oct. 1 shooting that killed 58 people.

A Las Vegas police spokeswoman gave a preliminary figure of $3.5 million for the agency's costs associated with the worst mass shooting in modern U.S. history. She noted the investigation is continuing.

Clark County spokesman Erik Pappa says fire department, coroner and social services costs so far could be $500,000.

Pappa says a facility dubbed the "resilience center" that provides resources and referrals for people affected by the shooting is expected to remain open for several years.

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