Cannot import and run with ts-node

[namlt3820]

I'm importing and using this module as

import { createPrivateKey } from "mnemonic-to-private-key/src/index";
const { address } = createPrivateKey();
console.log(address);

But running ts-node src/index.ts gave me this error:

import Mnemonic from "bitcore-mnemonic"
^^^^^^

SyntaxError: Cannot use import statement outside a module

What am I doing wrong here?