Economic powerhouse Taiwanese companies based in China may be forced to relocate if they feel "unjustly pressured," the island's vice president warned Tuesday after Chinese authorities launched a probe into tech giant Foxconn.Vice President Lai Ching-te, the current election frontrunner and head of the independence-leaning Democratic Progressive Party (DPP), warned that Taiwanese businesses might move out of mainland China if they feel "unjustly pressured".