Google is hiring thousands of people outside of its Silicon Valley base in the US and will build five more data centres in the country this year.In an investors' call, CEO Sundar Pichai said that Google would be "making significant investments in offices across nine states, including Colorado and Michigan".Google currently has six open data centres across the US. A data centre can typically employ a few hundred people, Fortune reported late on Friday.According to CNN, the company is also planning a "massive expansion" into San Jose, California, not far from its Mountain View headquarters.The announcement came after several reports said that Facebook, Apple and Amazon were also planning to build more facilities and hire more staff in the country.Riding on Google's growing ad business, Alphabet Inc on Friday posted $32.32 billion in revenue for the fourth quarter of 2017 -- up 24 per cent (year-on-year) from $26.06 billion during the same quarter in 2016.After deducting its traffic acquisition costs, Google's revenue alone was $25.87 billion.Google's Cloud business and its hardware revenue reached $4.69 billion, from $3.4 billion in Q4 of 2016.The company's Cloud business now generates over $1 billion per quarter, Pichai said during the investors' call.